2008: Problem 17

Topic: Dynamics
Concepts: Fictitious forces

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Solution:

We can go to the noninertial box frame by introducing a fictitious $-m\vec{a}$ force on the mass. This stretches the spring by distance

$$kx=ma$$

$$x=ma/k$$

which is also how much closer the mass moves toward the bottom. Thus, the answer is E.

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