Sample Ratio Problems

Introduction for sample ratio problems:

In mathematics, a ratio expresses the magnitude of quantities relative to each other. Specifically, the ratio of two quantities indicates how many times the first quantity is contained in the second and may be expressed algebraically as their quotient. Example: For every Spoon of sugar, you need 2 spoons of flour (1:2) (Source: Wikipedia)

In our daily life, by learning ratio and proportion many a times we compare two quantities of the same type. Thus, in convinced situations, comparison by division makes better sense than comparison by taking the difference. The comparison by division is the Ratio. We denote ratio-using symbol ‘:’. If two ratios are equal, we state that they are in proportion and use the symbol ‘:’ or ‘=’ to equate the two ratios.

Sample Ratio Definition and Example Problems:

Definition of ratio:

The learning ratio is a comparison by division method. We compare the two quantities in terms of ‘how many times’. This comparison is known as the Ratio. We denote ratio-using symbol ‘:’

Examples of sample ratio problems:

Sample problem 1:

Length and breadth of a rectangular field are 75 m and 25 m respectively. Find the ratio of the length to the breadth of the field.

Solution:

Length of the rectangular field = 75 m

Breadth of the rectangular field = 25 m

The ratio of the length to the breadth is 75: 25

The ratio can be written as

= 75 / 25 = 3:1

Thus, the required ratio is 3:1

Sample problem 2:

There are 60 persons working in an office. If the number of females is 25 and the left over are males, find the ratio of,

(a) The number of females to number of males.

(b) The number of males to number of females.

Solution:

Number of females = 25

Total number of workers = 60

Number of males = 60 – 25 = 35

Therefore, the ratio of number of females to the number of males

= 35: 25 = 7: 5

And the ratio of number of males to the number of females

= 25: 35 = 5: 7.

(Notice that there is a difference between the two ratios 7: 5 and 5: 7).I have recently faced lot of problem while learning Electric Field Definition, But thank to online resources of math which helped me to learn myself easily on net.

Sample Practice Problem for Ratio:

Problem 1:

In a bag of red and green sweets, the ratio of red sweets to green sweets is 3:5. If the bag contains 150 green sweets, how many red sweets are there?

Answer: There are 90 red sweets.

Problem 2:

A fence post in Tina's garden is 6 feet tall.  When she measured the fence post’s shadow, she found that it was 12 feet long.  A tree in Tina’s yard had a shadow of 72 feet.  How tall is the tree?

Answer: 36 tall is the tree

Problem 3:

The ratio of Kate's stickers to Jenna's stickers is 7:5.  Kate has 21 stickers. How many stickers does Jenna have?

Answer: 15 Stickers

Problem 4:

Chef Pillsbury's secret recipe requires 8 eggs for every 4 cups of flour. How many eggs will he need if he uses 6 cups of flour?

Answer: 12 eggs

Problem 5:

The ratio of the length of a rectangle to its width is 5:6. Its length is 25 inches. What is its width?

Answer: 30 inches

Introduction to Physics in Daily life

Physics is  a science based on experimental, observative and quantitative measurement. It is the study of nature and the laws governing the nature and how energy and matter are related to each other.

Physics in Daily Life Examples

Physics forms an inevitable part of all branches of life. It has numerous applications in all fields of life. If we consider our daily life, whatever we do can be directly or indirectly connected to one or the other principle of Physics. Our walking, our eating. our talking all involves Physics. Physics is the backbone of many daily life example like electricity, computer, wrist watch, Car, refrigerator and so on.Understanding Definition of Gravitational Potential Energy is always challenging for me but thanks to all math help websites to help me out.

some of the very few  examples from our daily life which illustrates the principles of Physics are

i. We walk, walk fast, run, jog, jump into a bus etc. All these or any type of motion is associated with Newton's law of motion.

ii. When we talk, our vocal cords vibrate producing sound.

iii. When we eat food, the chemical energy of the food is being converted into mechanical energy which we use to do different types of work.

iv. The electricity is our house is a gift of Physics. Hydroelectric project is the method in which water is used to generate electricity.  The mechanical energy of the water is converted into electrical energy using dynamo.



Physics in Daily Life, Examples Continued

v. refrigerator works on the principles of thermodynamics

vi. Pressure cookers, washing machines, music system, computers all work on the principle of Physics.

vii. Automobiles, trains, aircraft all work on the concepts of Physics.

viii. While you are reading this article the working of your eye is similar to the working of a camera which again belongs to Physics.

ix. Mobile phones working on microwaves also uses Physics to connect people from different parts of the world.

x. Writing using Pen, writing on whiteboard using marker all are the sole properties of Physics.

xi. Rain, snowfall, lightening, thunder, wind, sea breeze etc all owe their existence to the laws of Physics

As mentioned in the beginning, the above list is endless. Any phenomenon of our daily life you consider, we an surely bring Physics in it.

Physics Adding Vectors

Introduction to number of star activities:

Stars are the heavenly bodies like the sun that are extremely hot and have light of their own. They are made up of vast clouds of hydrogen gas, some helium and the dust. Hydrogen atoms are being continuously converted into helium atoms and a large amount of nuclear energy in the form of heat and light is released. The stars are not permanent. Some activities are continuously occurring in the core of the stars. Here we discuss the activities inside the stars.Please express your views of this topic Permanent Magnet Motor Free Energy by commenting on blog.

Activities Inside the Stars

As we know that the stars are not permanent, they have some internal activities. The activity begins with the gathering of hydrogen gas and helium gas present in galaxies to form the dense clouds of these gases. These stars are then formed by the gravitational pull and it becomes the protostar. It is a highly condensed cloud of gases, mainly hydrogen and some amount of the helium gas, formed by the gravitational contraction of gases present in the galaxy. It looks like a huge dark ball of gases. The formation of protostar is only a stage in the formation of the complete star. A protostar does not emit any light. The protostar continues to contract further due to the large gravitational gas cloud collide with one another very frequently. So, that the temperature of the protostar raises from - 173°C to 107 °C. At this high temperature, the nuclear fusion of hydrogen starts.Is this topic Examples of Electromagnets hard for you? Watch out for my coming posts.

4 1H1   `->`      2 He 4 + huge amount of energy

Now, the protostar begins to glow and become a complete star. It continues as a star for thousands of millions of years. In all the fusion reactions continues to liberate energy.

Conclusion for the Activities Inside the Stars

As in the star, the fusion reaction continues again in the interior of the star. Then it becomes the red giant star. At that time, it becomes red in color. After that, the future of the star depends on the mass of the star. If the mass of the star is same as that out sun it lose its expanding shell. The energy liberated by the fusion of helium would make this small core glow as white dwarf star. The matter is highly condensed. If the mass of the star is more than the mass of our sun, it continues to contracts and explodes, called the supernova. After that, it becomes the neutron star and then it becomes the black hole.

Define Electromagnetism

Define Electromagnetism
Advancement of modern physics is related to putting electricity and magnetism together to
get electromagnetism. It is governed by the fact that electric current has capacity to produce a
magnetic field. According to Faraday’s law, a change in electric field produce magnetic field and
change in magnetic field produces electric field. Scottish physicist Maxwell gave the complete
mathematical explanation of electromagnetism.I like to share this Definition of Electric Current with you all through my article.

Biot Savart Law Example
The electro magnet is the example of the Biot Savart Law. As we know that as the variable
current passes through a wire it produces a magnetic field. It can be observed in any household
by using a coil of wire connected to the AC source and put a magnetic or ferro magnetic material
near it. We will observe that the magnetic or ferromagnetic material is attracted towards the
coil until the coil is carrying the current. The attraction cease to exists as soon as current is
disconnected from the coil.

Mutual inductance formula
Mutual inductance is defined as production of electromotive force in a close coil due to change in
current in the coupled coil.
The induced electromotive force (Emf2) in coil 2 due to change in current (I1) in coil 1is given by
following formula:

Here M is mutual inductance.

Induction Heating Circuit
Induction heating circuit includes a work coil in which alternating current is induced using a high
frequency electricity. This induced alternating current produces intense and quickly changing
magnetic field within the work coil. This object or work-piece that is to be heated is then placed
under this alternating magnetic field. When placed within the alternating magnetic field, a current
flow is induced in the work-piece. These currents are eddy current that flow in small circles.

What is Induction Heating
Induction heating is the process of heating an electrically conductive material using alternative
magnetic field. It is a non-contact process of heating that use high frequency electricity to heat
the material. As mentioned, it is a non-contact process, hence the heating process does not
contaminate the heated material. As compare to other heating processes in which heat is
generated in heating element and then is used to heat the material, induction heating involves
generation of heat in the material, to be heated, itself. Hence induction heating is an efficient
process of heating.Having problem with Electrical Resistance Definition keep reading my upcoming posts, i will try to help you.

Electromagnetism Equations

Electromagnetism is governed by four basic formulas that are represented by Maxwell
Equations. These four Formulas are Gauss Law, Gauss Law in Magnetism, Faraday’s Law and
Amperes Maxwell Law.
These formulas are given below.
1. Gauss’a Law: it is given below
= Q/0

2. Gauss’s law in magnetism is given below:

=0

3. Equation for Faraday’s Law is given below:
= - (d

4. Ampere-Maxwell law formula is given below:
= µ0I+e0µ0 (d

The Relationship between Electricity and Magnetism

Electricity is related to both electrons and protons both carry a charge. Electrons carry positive charge
and protons carry positive charge. Protons concentrated in a small area called nucleus and placed in
the centre of atom. The motion of electrons is outside of nucleus in orbital. So, the moving of electrons
is response of Electricity. When an object is placed in magnetic field called magnet, it is due to motion
of electrically charged particles. Magnet has two poles called North poles and South poles. Two
magnets of same poles are repel each other while magnets of different poles are attracted each other.
Magnetism is a force of attraction or repulsion that acts at a distance. Electromagnetism definition is
correlated with electricity and magnetism each other.Please express your views of this topic Define Second Law of Thermodynamics by commenting on blog.

According to Dutch physicist Hendricks Anton Lorentz, Lorentz force law is the electric current applied
on a charged particle is parallel to the local electric field. The magnetic force, however, is perpendicular
to both the local magnetic field and the particle’s direction of motion. According to lenzs law, when an
electric force applied on a conductor then due to current it induced electromotive force. Lenz found a
way of direction of electromotive force and current of electromagnetic field. The direction of current
induced in magnetic field is opposite to direction of magnetic flux changes. The formula of Lenz law
shows negative sign to opposition of magnetic flux from the electric current.Is this topic Electric Flux Symbol hard for you? Watch out for my coming posts.

What is the Relationship between Electricity and Magnetism

Electromagnetism is also known to be as a Relationship between Electricity and Magnetism. Electricity
is produces due to magnetic effect and magnetism produces due to electric effect. When an electric
field is constant would never produce magnetism. Similarly when a magnetic field has constant value,
is doesn’t produce electric field. In our daily life we use many appliances based on electromagnetism
like television, computer etc. When an electric current is carried by a circular wire then magnetic field
produced will be same as magnetic field of bar magnet with their poles. When a magnetic field is linear
then circular electric field produces. When the electric current is carried in a straight wire then magnetic
field produces in a circular manner. Electricity and Magnetism equations are used to solve problems
related to daily life. Dr. Robert Becker was regarded as most well renowned scientist whose work
involved in the healthful and harmful effects of electromagnetic fields on the human body.

Electricity and Magnetism

How Induction Heating Works

For this a high frequency source is connected to the induction coil which generates high frequency
current in the coil. This in turn generates high and frequently varying magnetic field inside the induction
coil. The changing magnetic field induces a current in the targeted conductor. As a result of this large
amount of current passes through the target and it is known as eddy current. High frequency current
causes the skin effect which causes the AC to pass into a thin layer. Because of this effect resistance of
the target gets increased and leads to heating of target material through induction. During this process
induction coil does not get heated.Having problem with Wavelength to Frequency Equation keep reading my upcoming posts, i will try to help you.

Gravity Electromagnetism

Electromagnetism and gravity are two different forces in nature. Electromagnetism concerns with the
forces between electrically charged particles. Gravity is the attraction force between all bodies having
mass. Gravity is always attractive but electromagnetic force can be attractive or repulsive.

lenz's law equation

This is given as: V=- N

V is the induced emf due to change in flux φ.

N is number of turns of wire. The minus sign tells which way the induced current flows, based on the law
that magnetic field due to the induced current opposes the change in the flux that produced it.Please express your views of this topic Examples of Doppler Effect by commenting on blog.

Laws of Electromagnetism

Biot-Savart law: magnetic field generated due to a current carrying conductor of infinitely small
length dl is:
dB=(μo I dl sinθ) / 4πr2
Ampere's law: current generates magnetic field and its equation is given as:
∑B.dl=μo I

Force law: force on a charge q moving in a magnetic field B with velocity v is:

F =q)

Faraday's law: voltage induced in a circuit by change in magnetic flux is:
V=-

Induction Heating Coils

These coils are used in induction heating process to generate alternating magnetic field. Induction
heating coils are connected to a source of high frequency electricity which could produce high
Alternating Current through the coil. Induction coils are used to heat target material and induction coils

Biot Savart Law Derivation

Consider a small current carrying element of length dL with current I. Let r be the position vector of a
point P from the current element dL and θ be the angle between dL and r.

As per this law, the magnetic field dB induced at a point P due to current element depends on following
factors.

dBI
dBdL
dBsinθ
dB(1/r2)

Combining these we get

dBIdLsinθ/r2

dB=K Idl sinθ/r2

K=μ0/4π

Concept of Induction Heating System

Induction heating has unique characteristics of radio frequency, that portion of the electromagnetic
spectrum below infrared and microwave energy. Induction Heating System was discovered by Michael
Faraday by using electromagnetism. Since heat is transfer in form of electromagnetic waves, the object
never comes into contact with any flame directly, the inductor itself does not get warm, and there is
no product distortion. Induction Heating System becomes very repeatable and controllable. When an
alternating electrical current applying to primary coil transformer, a magnetic field is induced. If the
secondary coil of transformer is located within magnetic field, an electric current will be produced.
Induction Heating Systems used in new manufacturing circuit with accuracy, persistency and high
speed. In the process of Electromagnetism heat loss occurs, this loss of heat is transferred in the form
of production. The loss is converted in the form of unusable heating production, it is called Induction
Heating.I like to share this Define Electromagnetic Induction with you all through my article.

According to Lenz’s law explanation when a bar magnet moves toward solenoid from north pole then
the magnetic field lines move from south to north pole and the induced current moves from left to right
in the coil. When a bar magnet moves away from solenoid then direction of induced current changes.
Similarly if a bar magnet placed from South Pole towards solenoid then direction of induced current will
be right to left and magnetic lines move from north to South Pole.

Lorentz Force Law is the electric force apply on a charge particle is parallel to the local electric field. The
magnetic force is perpendicular to both the local magnetic field and the direction of particle’s motion.
The Lorentz force equation ir related to electromagnetism and Maxwell equation. Electric field and
magnetic field are related to each other and it’s superimpose effect is Definition of Electromagnetism.
When electric current applied on iron core wound with a conductor, the strength of electromagnet
depend on applying current. The current can easily start and stopped as required for functioning to form
an electromagnet.Understanding Magnetic Moment of an Electron is always challenging for me but thanks to all math help websites to help me out.

According to Biot Savart Law, Biot describes the magnetic field effect on electric current, how magnetic
field induced electric current. The law is consistent for both Ampere’s law and Gauss’ law and also valid
for magneto static approximation. Biot Savart Law Examples are based on electromagnetism; they
are used to define direction of current, magnetic field and electric field. It used for finding direction of
current and magnetic field and also finding length and accuracy.

Define Electromagnetism

Define Electromagnetism
Advancement of modern physics is related to putting electricity and magnetism together to
get electromagnetism. It is governed by the fact that electric current has capacity to produce a
magnetic field. According to Faraday’s law, a change in electric field produce magnetic field and
change in magnetic field produces electric field. Scottish physicist Maxwell gave the complete
mathematical explanation of electromagnetism.Having problem with electrolytic capacitor symbol keep reading my upcoming posts, i will try to help you.

Biot Savart Law Example
The electro magnet is the example of the Biot Savart Law. As we know that as the variable
current passes through a wire it produces a magnetic field. It can be observed in any household
by using a coil of wire connected to the AC source and put a magnetic or ferro magnetic material
near it. We will observe that the magnetic or ferromagnetic material is attracted towards the
coil until the coil is carrying the current. The attraction cease to exists as soon as current is
disconnected from the coil.

Mutual inductance formula
Mutual inductance is defined as production of electromotive force in a close coil due to change in
current in the coupled coil.
The induced electromotive force (Emf2) in coil 2 due to change in current (I1) in coil 1is given by
following formula:

Here M is mutual inductance.Please express your views of this topic Electric Circuit by commenting on blog.

Induction Heating Circuit
Induction heating circuit includes a work coil in which alternating current is induced using a high
frequency electricity. This induced alternating current produces intense and quickly changing
magnetic field within the work coil. This object or work-piece that is to be heated is then placed
under this alternating magnetic field. When placed within the alternating magnetic field, a current
flow is induced in the work-piece. These currents are eddy current that flow in small circles.

What is Induction Heating
Induction heating is the process of heating an electrically conductive material using alternative
magnetic field. It is a non-contact process of heating that use high frequency electricity to heat
the material. As mentioned, it is a non-contact process, hence the heating process does not
contaminate the heated material. As compare to other heating processes in which heat is
generated in heating element and then is used to heat the material, induction heating involves
generation of heat in the material, to be heated, itself. Hence induction heating is an efficient
process of heating.

Electromagnetism Equations

Electromagnetism is governed by four basic formulas that are represented by Maxwell
Equations. These four Formulas are Gauss Law, Gauss Law in Magnetism, Faraday’s Law and
Amperes Maxwell Law.
These formulas are given below.
1. Gauss’a Law: it is given below
= Q/0

2. Gauss’s law in magnetism is given below:

=0

3. Equation for Faraday’s Law is given below:
= - (d

4. Ampere-Maxwell law formula is given below:
= µ0I+e0µ0 (d

The Relationship between Electricity and Magnetism

The Relationship between Electricity and Magnetism

Electricity is related to both electrons and protons both carry a charge. Electrons carry positive charge
and protons carry positive charge. Protons concentrated in a small area called nucleus and placed in
the centre of atom. The motion of electrons is outside of nucleus in orbital. So, the moving of electrons
is response of Electricity. When an object is placed in magnetic field called magnet, it is due to motion
of electrically charged particles. Magnet has two poles called North poles and South poles. Two
magnets of same poles are repel each other while magnets of different poles are attracted each other.
Magnetism is a force of attraction or repulsion that acts at a distance. Electromagnetism definition is
correlated with electricity and magnetism each other.I like to share this Electric Flux Units with you all through my article.

According to Dutch physicist Hendricks Anton Lorentz, Lorentz force law is the electric current applied
on a charged particle is parallel to the local electric field. The magnetic force, however, is perpendicular
to both the local magnetic field and the particle’s direction of motion. According to lenzs law, when an
electric force applied on a conductor then due to current it induced electromotive force. Lenz found a
way of direction of electromotive force and current of electromagnetic field. The direction of current
induced in magnetic field is opposite to direction of magnetic flux changes. The formula of Lenz law
shows negative sign to opposition of magnetic flux from the electric current.



I have recently faced lot of problem while learning 0th Law of Thermodynamics, But thank to online resources of math which helped me to learn myself easily on net.

What is the Relationship between Electricity and Magnetism

Electromagnetism is also known to be as a Relationship between Electricity and Magnetism. Electricity
is produces due to magnetic effect and magnetism produces due to electric effect. When an electric
field is constant would never produce magnetism. Similarly when a magnetic field has constant value,
is doesn’t produce electric field. In our daily life we use many appliances based on electromagnetism
like television, computer etc. When an electric current is carried by a circular wire then magnetic field
produced will be same as magnetic field of bar magnet with their poles. When a magnetic field is linear
then circular electric field produces. When the electric current is carried in a straight wire then magnetic
field produces in a circular manner. Electricity and Magnetism equations are used to solve problems
related to daily life. Dr. Robert Becker was regarded as most well renowned scientist whose work
involved in the healthful and harmful effects of electromagnetic fields on the human body.

Bernoulli's Principle

Bernoulli's Principle

Daniel Bernoulli was the one who formulated the Bernoulli principle.The Bernoulli's Principle Definition states a relation b/w v, p and h of non viscous fluid. The flow is horizontal in nature. Here p is the
pressure, v is the velocity and h is the height.

According to the Bernoulli principle the v and p of the fluid that is flowing are inversely proportional to each other, that is if the velocity would increase then it will lead to a decrease in the pressure of the
fluid.I like to share this Atomic Mass of Oxygen with you all through my article.

Bernoulli principle equation can be stated as:

P / p g + v2 / 2 g + z = K

This is called Bernoulli's Principle Equation where

P / p g = pressure energy per unit weight fluid or pressure head.

V2 / 2 g = kinetic energy per unit weight or kinetic head.

z = potential energy per unit weight or potential head.

Here

P = pressure, p = rho

There are quite many Bernoulli's Principle Examples. Let us just take a simple one. Consider the air plane flying. How is it possible? Have you ever thought about it? Well the answer lies in the Bernoulli principle
which is kept in mind while designing the wings so that the pressure exerted from below the wings is greater than that exerted from the top and the plane rises up in the sky. Even you can consider the cars

whose tires are built in such a manner that during racing the pressure is exerted such that the car remains on the track.Understanding Absorbance Units is always challenging for me but thanks to all math help websites to help me out.

Bernoulli principle is also used in designing of scientific devices like Venturi meter. It is also used for making orifice meter. Have you heard  about the pilot tube, yes it is also based on the same principle. The
venture in the carburetor of the vehicles also works on this principle. Channel hydraulic is another area of application.

Like these there are endless applications and many are yet to be discovered. All of these come under fluid flow. So when we consider the fluid flow we can assume that this principle will be applied and
hence sum of all the components acting in a particular direction would remain constant whatsoever. This is an important implication of  Bernoulli principle and should be remembered. We can consider the
movement or the flow of both types of liquids that is viscous liquids and also the non viscous flow. It is important to note that the type or nature of liquid may affect the pressure etc. but overall they remain constant.

Standard for Atomic Mass

Introduction to standard for atomic mass:

Atomic mass is the mass of a single atom and it is usually expressed in atomic mass units (or amu). Most of the atomic mass is concentrated in the nucleus, in the protons and neutrons contained. Since each proton or neutron weighs about 1 amu, the atomic mass is always very close to the mass number (or the total number of protons and neutrons in the nucleus). The atomic masse is usually determined by mass spectrography and the atoms of the isotopes of an element have the same atomic mass. It has been determined with great relative accuracy, but its absolute value is less certain.Looking out for more help on Carbon Atomic Mass in algebra by visiting listed websites.

Standard Atomic Mass

Atomic mass is the mass of an atom or molecule on a scale where the mass of a carbon-12 (12C) atom is exactly 12. Atomic mass or the mass of any atom is approximately equal to the total number of its protons and neutrons multiplied by the atomic mass unit (u) which is 1.660539 × 10-24 gram since electrons are much lighter. The atoms do not differ much from this simple formula, but only by less than 1%.

Atomic mass unit or amu

Atomic mass unit or amu is the unit defined as exactly 1/12th of the mass of a carbon-12 atom. The carbon-12 is an isotope of carbon with six protons and six neutrons in its nucleus. One amu is equivalent to 1.66 × 10−24 grams or 1.66 × 10--27 kg, approximately. The masses of individual atoms are expressed in terms of Atomic Mass Unit or amu. The standard is the unit of mass equals to one-twelfth the mass of the carbon atom, having as nucleus the isotope with mass number 12. Atomic mass unit has the abbreviation as amu and also known as dalton. I am planning to write more post on Rotational Energy, The first Law of Thermodynamics. Keep checking my blog.

Atomic Mass of Isotopes:

The discovery of isotopes complicated the situation. For example, pure oxygen is composed of a mixture of isotopes in nature and some of the oxygen atoms are more massive than others. This was not problem for the calculations since the relative abundance of the isotopes remained as the same [or constant]. In such cases, the average mass of its atoms expressed in amu is taken as the relative atomic mass of a chemical element.

Magnetic Field of the Earth

Introduction to Magnetic field of earth

Sir William gilbert was the first to suggest in year 1600, that earth itself is a huge magnet. His statement was based on the following evidence:

I. A magnet suspended from a thread and free to rotate in the horizontal plane comes to rest along the north-south direction. On disturbing, the magnet returns quickly to its north-south direction. This is as if a huge magnet lies along the diameter of earth. The north pole of this fictitious magnet must be towards geographical south so as to attract south pole of the suspended magnet and vice-versa.

II.When a soft iron piece is buried under earth’s surface in the north south direction, it is found to acquire the properties of a magnet after some time.I like to share this Magnets Rare Earth with you all through my article.

III.When we draw field lines of a magnet, we come  across neutral points. At these points, magnetic field due to the magnet is neutralized or cancelled exactly by the magnetic field of earth. If earth has no magnetism of its own, we would never observe neutral points.

Cause of Magnetic Field of the Earth

The exact cause of earth magnetism is not yet known. However, some important postulates in this respect are as follows:

a) According to Prof. Brackett, earth’s magnetism may be due to rotation of about its axis. This is because every substance is made up of charged particles. Therefore, a substance rotating about its axis is equivalent to circulating currents, which are responsible for the magnetization.

b)In the outer layers of the earth’s atmosphere, gases are in the ionized state, primarily on account of cosmic rays. As earth rotates, strong electric currents are setup due to movement of ions. These currents might be magnetizing the earth.Is this topic Transverse Waves and Longitudinal Waves hard for you? Watch out for my coming posts.

c)The earth’s core is very hot and molten. Circulating ions in the highly conducting liquid region of the earth’s core could form current loops and produce a magnetic field.

General Features of Earth’s Magnetic Field

It has been established that earth’s magnetic field is fairly uniform. The strength of this magnetic field at the surface of earth is approximately 10-4 tesla or 1 gauss. The field is not confined only to earth’s surface, it extends upto a height nearly 5 times the radius of earth.  At present the south pole of earth is located at a place on north Canada, longitude 960 W and latitude 70.50 N and the north pole is located diametrically opposite the south pole i.e. at longitude 840 E and latitude 70.50 S. The magnetic poles are approximately 2000 km away from geographic poles.

Conservation of Kinetic Energy

Introduction to Conservation of kinetic Energy:

Have you ever observed a ball when thrown vertically upward with certain force? It goes to a certain height and comes back to the ground when it strikes the ground it bounces back in upward direction once again. Do you know what different forms of energy are involved here and what energy conversion is going on in this motion? Before understanding this, let us try to understand what Conservation of Energy is.

For an isolated system, the total amount of energy remains conserved. In other words we can say that energy can neither be created nor destroyed, it can only be changed from one form to the other. Conservation of energy tells that the total amount of energy remains unchanged. However, during a process or activity one form of energy may get changed to the other form, but if you calculate the total amount of energy, it will remain conserved.

Conservation of Energy when Ball Going Up

For an example If a is ball thrown vertically upward. Using our muscle energy, we provide some kinetic energy to ball and ball starts moving with this kinetic energy in upward direction. As the ball goes up its kinetic energy starts converting into potential energy. As a result the kinetic energy of the ball start decreasing and potential energy of the ball starts increasing. Due to decrease in kinetic energy, the velocity of the keeps on decreasing and finally at one point it becomes zero. This is the highest point up to which ball can go. At this point the total kinetic energy of the ball has converted into potential energy.
.

Thus at highest point, ball has no kinetic energy and highest potential energy. It is interesting to know that the potential energy as this point is equal to initial kinetic energy of the ball. This is as per the conservation of energy because kinetic energy is converted into potential energy but total amount of energy remains same.

Conservation of Energy when Ball Falls Down

Now ball starts falling down with this potential energy and as it falls down under gravity, its potential energy starts converting into kinetic energy. As a result the potential energy decreases and kinetic energy increases and velocity of the ball goes on increasing. The moment when ball strikes the ground, all its potential energy is converted into kinetic energy and once again due to conservation of energy, this energy is equal to the potential energy at the top as well as to the initial kinetic energy.

Electrical Current Production

Introduction to electrical current production:

Electric current is defined as the migration of electric charge. The electrical current may consist of charged particles that are in motion of any origin; a majority of these comprise electrons. The flow of charged particles forming the electrical current may be in either of the direction or sometimes in both the directions simultaneously.

                                                                Image flow of electron

How is Electrical Current Produced

Current is usually generated by the electromechanical generators which are run by steam obtained from the combustion of fossil fuels or in some cases by the heat that is discharged from the nuclear reactions or production of the current is possible from various other sources such as kinetic energy which is extracted from running water or from wind. Steam turbines produce up to 80% of the electrical current using a large variety of sources. Continuous production of electrical current is required since very large quantities of current cannot be stored that may be required for meeting the large-scale demands of the nation. Generation of electrical current from renewable sources such as hydropower and wind are gaining importance due to concerns with regard to the environment.


Some other Sources of Production of Electrical Current
Burning of fossil fuels such as natural gas, coal, crude oil occurs in the power plants where most of the electric energy is generated. This massive production accounts for the gases emitted into the earth’s atmosphere from the green houses gases. The heat that is produced by burning fuel is generally utilized for the evaporation of huge volumes of water, creating steam that is required by the steam turbine where it is converted into mechanical work. This mechanical work is efficiently converted into electrical current by connecting the drive shaft of the turbine to the mechanical generator.
Using an electrochemical generator for the production of electrical current: An electrochemical generator with a cell that contains an anode compartment and an aqueous solution in motion. The active metallic material loses electrons after being oxidized, which is collected through the anodic electron collector.

                                                     Image of electrochemical generator

Conclusion for Production of Electrical Current

To conclude, electrical current is produced from a variety of sources that range from fossil fuels to wind or water. A change in the magnetic field results in a change in the flux, resulting in the production of electrical current.

Alternating Current Motors

Introduction to Alternating Current Motors:

The electric motor which works under the alternating supply of current is named as the alternating current motor. As the name suggest this motor is driven only by the alternating current and if one give a direct current to the motor then the motor does not work or may get damaged. The alternating current motor consists of two major but the basic parts as, the stator which is generally fixed outside and is stationary but there exists some motor which have the stator fixed within it and the second part is rotor, which is connected both inside and outside the motor. The outside rotor is used to increase the inertia and the cooling of the motor. The outside stator has the coils to which the alternating current is supplied to produce a rotating magnetic field in the coil. The inside rotor is attached to the output shaft of the motor which gives a torque due to the rotating magnetic field. The alternating current motor of a ceiling fan is shown in the fig.1.

                                                   Fig.1 Alternating current motor of ceiling fan

Types of Alternating Current Motors

Without considering the eddy current motors, while going through the alternating current motors, alternating current motors are broadly has two types:

Synchronous motors:  These alternating current motors are the simplest kind of the alternating current motors. They rotate at a frequency which is either exactly same as the supply frequency or is a multiple of the supply frequency. In these motors the magnetic field which is generated on the rotor is either due to the current which is delivered through the slip rings or due to a permanent magnet.
Induction motors: These alternating current motors are also the simple alternating current motors but they rotate at a frequency slightly less than the supply frequency. Thus these motors run slowly. In these motors, the magnetic field which is generated on the rotor is only due to the induced current inside the coil of the motor.


Conclusion on Alternating Current Motors

From the discussion we made on alternating current motors, we conclude the importance of alternating currents and its varied application in day to day life.

Ferromagnetic Domains

Introduction to ferromagnetic domains:
The ferromagnetic substances are those in which each individual atoms or molecules or ions have a non zero magnetic moment as in the paramagnetic substances. When the ferromagnetic substances are placed in an external magnetizing field, they get strongly magnetized in the direction of the field. Ferromagnetism has been explained by Weiss on the basis of domain theory in addition to the usual electron theory.Please express your views of this topic Ferromagnetic Metals by commenting on blog.

Domains in Ferromagnetic Substances

The each atom of a ferromagnetic substance is a tiny magnetic dipole having permanent dipole moment. However in ferromagnetic materials, atoms form a very large number of small effective regions called domains. Each domain has a linear dimension of 1000 A° and contains about 1010 atoms. Within each domain a special interaction called exchange coupling renders dipole moments of all the atoms in a particular direction. Thus each domain is a strong magnet without any external magnetic field. In spite of this, a ferromagnetic substance does not behave as a magnet, because in the absence of the external magnetic field, the magnetic moments of the different domains are randomly oriented so that their resultant magnetic moment in any direction is zero.Is this topic Permanent Magnet Generator for Sale hard for you? Watch out for my coming posts.

When an external magnetic field is applied on the ferromagnetic substance, it gets strongly magnetized. This can be explained as follows:

(i) Displacement of boundaries of the domains, i.e., domain which are oriented in the direction of the applied field increase in size and the domains which are oriented opposite to the field deceases in size.

(ii) Rotation of domain, i.e., the domain rotate till their magnetic moments are aligned in the direction of the applied magnetic filed. This would happen only when the magnetic field applied is very strong.

                                                   Image of the ferromagnetic domains

Conclusion for the Ferromagnetic Domains

From the above discussion we can say that when the domains have aligned along the magnetic field and amalgamated to form a single giant domain. This is how ferromagnetic material gets strongly magnetized in the direction of the applied field. The examples of the ferromagnetic materials are iron, cobalt, nickel and some are the rare earth materials as gadolinium and dysprosium.