Initially sliding with a speed of 2.1 m/s, a 2.1 kg block collides with a spring and compresses it 0.35 m before coming to rest. What is the force constant of the spring?

Answer 1

InitialKE= 1/2 m v^2

1/2 kx^2= KE=1/2 mv^2
k= mv^2/x^2