big five powers

A contractor wishes to lift a load of bricks from the sidewalk to the top of a building by means of a winch. Since we know the expression for work, we can calculate work to be done by the force applied by the winch to lift the load. We are interested in the rate at which it is done, that is, ..

Advantages - The demand for electricity varies at different times of a year. One big disadvantage is that the wind, waves and tides do not occur at all time and hence cannot guarantee steady production of electricity. Hydroelectric power stations can solve this problem. When the..

Electricity is obtained from flowing water. The flow of water is checked by building a dam. The water from the dam is allowed to flow through the tunnels at a high pressure. Turbines convert the potential energy of the water into electricity. About 23,800 MW of energy is generated by hydel pow..

Ability of the lens to converge a beam of light falling on the le..

Power is the rate of doing work or in other words, it is the work done in one second. If a current of 'I' amperes flows through a conductor of resistance 'R' ohm for a time 't' seconds when the potential difference across its ends is 'V' volt, then the electric power consumed P..

Whenever a ray of light passes through a lens (except when it passes through the optical centre) it bends. The bending of light rays towards the principal axis is called convergence and bending of light rays away from the principal axis is called divergence. The degree of convergence or divergence..

The ability of the instrument to resolve the images of two point objects lying close to each other. Due to the wave nature of light each point object produces its own diffraction pattern, which overlap, and the image can no longer be identified. Resolving power of a microscope is the reci..

The tides are formed due to the gravitational force of attraction between the earth, sun and moon. During high tides sea water is trapped in a reservoir, and released later to drive turbines, which in turn produces electricity. The block diagram given below illustrates the transformation of energy..

Hydroelectric Power Plants - The electricity produced from flowing water is called Hydroelectric power. The world's first hydroelectric power plant was set up in 1882 in Wisconsin USA. It had a very small output, supplying power only for about 250 light bulbs..

Power of a Lens - Ability of the lens to converge a beam of light falling on the le..