Physics
Assertion (A): When a hammer is made to fall on a nail fixed upright on a wooden piece, the nail begins to penetrate the wood.
Reason (R): As the hammer starts falling, its kinetic energy begins to change into potential energy.
- Both A and R are true and R is the correct explanation of A.
- Both A and R are true and R is not the correct explanation of A.
- assertion is false but reason is true.
- assertion is true but reason is false.
Answer
assertion is true but reason is false.
Explanation
Assertion (A) is true. When a hammer is made to fall on a nail fixed upright on a wooden piece, the nail begins to penetrate the wood due to the force applied by the falling hammer.
Reason (R) is false. The statement about the conversion of kinetic energy into potential energy as the hammer falls is incorrect. Potential energy is the energy that is stored in an object due to its position above the earth's surface. Hence, when a hammer is lifted it stores potential energy in it and when the hammer starts falling, this potential energy begins to change into kinetic energy and is used in driving a nail into the wood.
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