A 65-kg person stands on a scale in a moving elevator while holding a 5.0 kg mass suspended from a massless spring with spring constant 1.08 kN/m . None of the objects in the elevator is moving relative to the elevator, but the spring is stretched by 6.0 cm .?

The question is incomplete. However, I believe, it is asking for the acceleration of the elevator. This is 3.16 m/s².

Explanation:

By Hooke's law,

F is the force on a spring, k is the spring constant and e is the extension or compression.

From the question,

This is the force on the mass suspended on the spring. Its acceleration, a, is given by

This acceleration is more than the acceleration due to gravity, g = 9.8 m/s². Hence the elevator must be moving up with an acceleration of

12.96 - 9.8 m/s² = 3.16 m/s²

positive reinforcement? ?