Physics- Problems on work,energy power and momentum

A horizontal spring whose spring constant is 640 N/m is lying on a frictionless surface. One end of the spring is attached to a wall, and the other end is connected to an object of mass 8 kg. The spring is then compressed by 41 cm and released from rest. What is the speed of the object at the instant when the spring
is stretched by 27 cm relative to its unstrained length?
How can i do this question? The answer is 2.76m/s


1/2 * 640 * (0,27)² = 1/2 * 8 * v²
2,4 m/s = v

My answer is pretty close, idk why the problem mentioned 41cm as the max compression, so there’s probably another way to solve using it that i am not familiar with

1 Like

Hey,i got the same answer too but got confused seeing the answer key. Thank you for clearing :hugs:

1 Like