Question

when a spring is compressed by 3cm; it's potential energy is U. when it is compressed by 6cm; it's potential energy will be
I) U
2) U
3)4 U
4) 3 U
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Answer 1

Answer ⇒ 2U (Option b. Not clearly mentioned there, but i think its an typing error in question.)

Explanation ⇒ Potential energy of the spring = kx

∴ U = k(3)

∴ k = U/3

Let the final potential energy be U',

then,

U' = kx₂

∴ U' = k(6)

∴ U' = 6k

∴ U' = 6(U/3)

∴ U' = 2U

Final potential energy is 2U.

Hope it helps.

Answer 2

Answer:

Explanation:

U = k(3)

∴ k = U/3

Let the final potential energy be U',

then,

U' = kx₂

∴ U' = k(6)

∴ U' = 6k

∴ U' = 6(U/3)

∴ U' = 2U