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

Answer:

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$=\mu g$

$v^2-u^2=2as$

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

$v_i=\sqrt{2(\mu g)d}$