ENERGY - IN A NEW ANGLE

A car is running. It can hit and damage an object. It can do some work because it posses energy. A body gets energy by virtue of its motion or its dynamics. We know, it is called kinetic energy. The formula is 1/2 mv^2, m is the mass of the body, or we can say m is the inherent property of the body. v is the velocity of the body. or we can say v represents the dynamics of the body. Almost all the kinetic energy formula in physics follows this pattern.

Consider an oscillating spring. It is KE is 1/2kx^2. Here k is constant (property) of the spring. It depends on the material, thickness, and length of the spring. x is the maximum displacement of the spring from its rest position. We say x represents the main dynamics of the spring.

Consider a rotating body. Its K.E is 1/2IW^2. I is the moment of inertia or property of the rotating body, w its angular velocity (dynamics).

The energy stored in an inductor (coil of wire) is 1/2LI^2. L is the inductance or the magnetic property of the coil. I is the current flowing through it (dynamics).

The energy of the capacitor is 1/2cv^2. c is the capacitance of the capacitor (property). v is the voltage applied across it (electrical dynamics - in a capacitor voltage plays, more important role than a current).

The kinetic energy of the running fluid is 1/2dv^2. Here d is the density of the fluid and it is the main property of fluid and not the mass.

Einstein said the energy of a body is mc^2. m is property of the body, we understand. But c is the velocity of light, why it appears here? When the body explodes and destroys itself, all the particles in it are converted into electromagnetic waves and they move with the velocity light. Next, why 1/2 is not present here? The energy of a body is the sum of rest energy and the energy when it is moving. Hence 1/2+1/2 =1. We have looked at the famous Einstein formula from a new angle.

Finally, when a body is active, its energy will be equal to = 1/2 * inherent property*(main dynamics)

This formula will help us understand the nature of energy and make new formulas in new situations.

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