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Work and Energy — Science STD 9 — Question

Maharashtra BoardEnglish MediumSTD 9ScienceWork and Energy3 Marks
Question
Explain by an example what is meant by potential energy. Write down the expression for gravitational potential energy of a body of mass m placed at a height h above the surface of the earth.
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Answer

Potential energy: The energy of a body due to its position or change in its shape is known as its potential energy.
Example: A stretched rubber has potential energy due to change in its shape and water in the overhead tank has potential energy due to its height above the ground.
PE = m × g × h
where, PE is the potential energy of the body.
m is the mass of the body.
g is the acceleration due to gravity.
h is the height above the surface of earth.

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