Question:
The potential energy of a long spring when stretched by 2 cm is U. If the spring is stretched by 8 cm the potential energy stored in it is:
The potential energy of a long spring when stretched by 2 cm is U. If the spring is stretched by 8 cm the potential energy stored in it is:
Updated On: Oct 20, 2023
4U
\(\frac U8\)
16U
\(\frac U4\)
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The Correct Option is C
Solution and Explanation
\(U = \frac 12K(2)^2 = 2K\)
\(U' = \frac 12K(8)^2 = 32K\)
Now,
\(\frac {U'}{U} = \frac {32K}{2K}\)
\(\frac {U'}{U} = 16\)
\(U' = 16U\)
So, the correct option is (C): 16U
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