Question

An object of mass m is sliding with speed vi at some instant across a level tabletop, with which its coefficient of kinetic friction is µ. It then moves through a distance d and comes to rest. Which of the following equations for the speed vi is reasonable?

A) vi = v2µd
B) vi = v2µmgd
C) vi = v-2µmgd
D) vi = v-2µgd
E) vi = v2µgd

Answer 1

Step-by-step explanation:

Given

initial speed
`=v_i`

coefficient of kinetic friction
`=\mu`

It moves a distance d after that it comes to rest

acceleration offered by table top
`=\mu g`

`v^2-u^2=2as`

`0-(v_i)^2=2(-\mu g)d`

`v_i=√(2(\mu g)d)`