$2$uestion $3$

A block of mass $m=4kg$ starts from point. A with speed $v_0=10mls,$ it slides to $B$ along a track that ascends through height $h=2m.$ The block then runs into and compresses a horizontal relaxed spring with force constant $k=400\frac{N}{m}$ until it momentarily stops at point $C.$

The distance between A and $B$ is $d=8m.$ A constant friction force $f_k=6N$ acts on block between A and $B$ but no friction between $B$ and $C($take $g=10\frac{m}{s^2})$

a$)$ What is the speed of block when it reaches B$?$

b$)$ What is elastic potential energy of compressed spring?

$=>$ What is distance that spring is compressed when the block momentarily stops at C$?$

d$)$ What is the change in thermal energy of block$-$track system?