Thank you for pointing out the error.
I have gotten that the Ek system= 50/t (aka. 50/(mw+mb)
And now I set the total kinetic energy to equal elastic energy plus work done by friction?
Ek=energy lost + Ee
The one thing that I don't understand about that is wouldn't the block also be using...
Homework Statement
A 50g bullet traveling horizontally at 200 m/s embeds itself in a wooden block, initially at rest, on a horizontal surface (μk=0.1). The block slides 1.2m toward a spring and collides with it. The block compresses the spring (k=600 N/m) by 20 cm. Find the mass of the wood...