Showing posts with label Electricity. Show all posts
Showing posts with label Electricity. Show all posts

Wednesday, May 22

Static Electricity Materials


Static Electricity

Static electricity is the accumulation of excess charge on the surface of an insulator, that is, a material that does not conduct electricity.

Why does the charge accumulate?

An atom is made of a positively charged nucleus (made of protons and neutrons) surrounded by several shells of electrons which are negatively charged. Objects that we see everyday are made of electrically neutral atoms or molecules. This means that the number of positive charges and negative charges are equal. However, when two electrically neutral materials are in contact, the electrons may move from one material to another. This means that one material gets an excess of negative charge, while the other one gets an excess of positive charge. If you separate the materials after the electrons have moved, there will be a charge imbalance in the materials.

In a conducting material, the charges are immediately conducted away, and the charge does not accumulate. So, the phenomenon of static charge accumulation or static electricity can be seen only in insulators or non-conductors.


Experiments of static electricity materials:


You can see how static charges accumulate by doing these simple experiments.

Experiment 1:

Rub a balloon vigorously on a sweater.  The rubbing motion increases the area of contact between the two surfaces, making it easier for charges to migrate. The balloon gets negatively charged and the jumper aquires a positive charge. Now, if you bring the balloon close to your hair, your hair will cling to the balloon. This is known as static cling.

Experiment 2:

Use a plastic comb to comb through your hair about ten times. Now, turn on a tap so that you have a steady water flow. The flow should not be very fast. If you bring the comb near the stream of water without touching it, the water will bend towards the comb. This is because the charges on the comb pull on the uncharged water.

Removing static electricity:

Static electricity can be removed by bringing the material into contact with a conductor, or with a region that has an excess charge that is opposite to the material. This causes the charge to neutralize, resulting in a static 'shock.' In regions of high humidity, the air itself will conduct away the static charges.

Wednesday, March 27

Electricity Generation From Water


Introduction:

Electricity can be generated from water in two methods; one is the method where we use the potential energy of the water in dams using the water wheels. The other source of energy is capturing the energy from the ocean waves. The energy generated by the water is a renewable energy, as we know that water is present abundantly in the nature and there is no consumption of water during the generation of electricity from the water. Most of the countries rely on this method that is production of electricity using water because it is a renewable energy resources and gives sustainable energy.  The energy generated by the water is termed as the hydro electricity.


Sources of electricity generation


Dams: In this case whenever a dam is built at the beginning itself the tunnels are built where the water flows and these tunnels are lined with turbines. As we let out the water to flow through these tunnels the water flows over the turbines which are lined along the tunnels.As a result these turbines rotate,and thus electricity is generated.

Ocean waves: The electricity generated from the ocean is known as ocean wave power because this energy is generated by the oceanic waves. This is the process where the tidal energy is used to generate the electricity, whenever there is a high tide on the sea shore or the oceans there is lot of energy in these waves which is converted into electricity by running of the turbines. The water from the tides is stored and then this water is left over the turbines which in turn produce the electricity.


Run of the river: This is process where the natural elevations on the rivers are made use to produce the electricity. In this case the water is made to fall on the turbines which are placed at the bottom of the elevation of the river, it can be a natural or a man made elevation on the river. Here also the turbine are used to produce the electricity.