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:

A spring of force constant 800 N/m has an extension of 5 cm. The work

1.	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:
Answer» 16 J 8 J 32 J 24 J Solution :Here the WORK done in stretching a spring is stored as the potential ENERGY of the spring. THUS `W = 1/2k_2x_2^2 - 1/2 k_1x_1^2 = 1/2k(x_2^2 - x_1^2) = 1/2 xx 800[(15/100)^2 - (5/100)^2] = 8J`.

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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:

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