For definition of kinetic energy of a body increase body weight by a square of its speed and divide result into 2. The potential energy of the body raised over the Earth's surface is equal to the work of body weight on height of its rise and acceleration of gravity. There is also potential energy is elastic the deformed body.

## It is required to you

- scales, the device for determination of speed, a ruler or a roulette

## Instruction

1. Definition of kinetic energy of a body Measure body weight in kilograms on scales or any other method, for example, by means of interaction with a standard. After that measure body speed. If the body does not move, then its kinetic energy is equal to zero. Measure instantaneous velocity by means of a speedometer, or the special radar. To find the constant speed, distance which passed a body divide into that time which it was en route. If the body moves uniformly accelerated from a condition of rest, then for finding of speed the doubled distance which the body passed for some time, divide into this time in seconds. Measure all distances in meters, and speeds in meters per second. After that square value of speed of a body and increase by body weight, and divide result into two and receive value of kinetic energy in Joules.

2. Determination of potential energy of the body raised above the ground Find body weight in kilograms any of the described ways. After that, measure height on which the body, in meters is raised. Multiply the obtained data and still increase them by the acceleration of gravity which is 9.81 m / с2. As a result receive potential energy of the body raised on some height over the Earth's surface in Joules.

3. Potential energy it is elastic the deformed body deformed to a telaizmerta rigidity if it is in advance unknown. For this purpose by means of a dynamometer deform a body, having changed its sizes to some length. The dynamometer will show elastic force, and measure deformation by means of a ruler or a roulette. Having divided value of force in Newtons into deformation in meters, receive value of rigidity. For calculation of energy the change of the sizes of a body at deformation measured in meters is elastic the deformed body, we square and we multiply by value of rigidity. We divide the received number into 2.

4. Total mechanical energy of a telayesla a body has at the same time both kinetic and potential energy, for example, the flying plane, for finding of total mechanical energy just put them.