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A spring of force constant 800 N/m has an extension of 5 cm. The work done in extending it from 5 cm to 15 cm is

1. 16 J
2. 8 J
3. 32 J
4. 24 J

Correct answer: 8 J

Solution

The work done on a spring is calculated using the formula W = (1/2)k(x2² - x1²), where k is the spring constant and x is the extension. By substituting the values for the initial and final extensions (0.05 m and 0.15 m) into the formula, the work done is found to be 8 J.

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