Question

The potential energy, P, in a spring is represented using the formula P = A equals StartFraction one-half EndFraction b h.kx2. Lupe uses an equivalent equation, which is solved for k, to determine the answers to her homework.

Which equation should she use?

k = 2Px2
k = k equals StartFraction one-half EndFraction P x squared.Px2
k = k equals StartFraction 2 P Over x squared EndFraction.
k = k equals StartFraction P Over 2 x squared EndFraction.

Answer 1

Start with P = (1/2) k x^2.
Multiply both sides by 2: 2P = k x^2.
Divide by x^2: k = 2P / x^2.

So the correct choice is: k = (2P)/(x^2).