1.

A `2kg` block slides on a horizontal floor with the a speed of `4m//s` it strikes a uncompressed spring , and compresses it till the block is motionless . The kinetic friction force is compresses is `15 N` and spring constant is `10000 N//m` . The spring byA. `2.5`B. `11.0`C. `8.5`D. `5.5`

Answer» Correct Answer - D
Let the spring be compressed by `x`.
Loss in `KE` of block
= Gain in `PE` of spring + Work done against friction
`rArr (1)/(2) xx 2 xx4^(2) =(1)/(2) 1000 x^(2) + 15 x`
On solving, we get `x = 5.5 cm`.


Discussion

No Comment Found

Related InterviewSolutions