Question

A 0.4 kg block with initial speed of 0.8m/s slides along a horizontal table against a friction force 0f 0.70. How far will it slide before stopping?

Answer 1

acceleration=ma=.70

.4×a=.70

a=1.75

this acceleration will be responsible to stop the block

so

0=.8-1.75×t

t=8/17.5

t=.4s( approx)

hope it helps you