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Question
Justify the statement, “Work and energy are the two sides of a coin.”
Solution
- Work and energy both are scalar quantities.
- Work and energy both have the same dimensions i.e., [M1L2T-2].
- Work and energy both have the same units i.e., SI unit: joule and CGS unit: erg.
- Energy refers to the total amount of work a body can do.
- A body capable of doing more work possesses more energy and vice versa.
- Work done on a body by a conservative force is equal to the change in its kinetic energy.
Thus, work and energy are the two sides of the same coin.
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