Question

A block slipping on a rough horizontal plane moves with deceleration of $4.0m/s^2$. The coefficient of kinetic friction between the blocks and the plane is:

• A. 0.4
• B. 0.3
• C. 0.2
• D. 0.1

Answer 1

Answer: (A)

0.4

The friction force $=F=ma$

where $m$ is mass and $a$ $=$ deceleration of the body$=4.0m/s^2$

so $f=4mN$

Normal force$=$ weight of the body $=mg$

So coefficient of kinetic friction $4m/mg$

$=4/g$

$=4/10$

$=0.4$

Hence the coefficient of kinetic between the block and lane is $0.4$

Hence,

option $\left(A\right)$ is correct answer.