Answer to Question #289858 in Physics for Muaz jemal

Question

A BODY HAS A MASS OF 15KG AND IT IS BEING PUSHED HORIZONTALLY WITH A FORCE OF 100N IF IT HAS A COEFFICIENT OF KINETIC FRICTION 0.3 THEN WHAT IS THE ACCELERATION OF THE BODY)

Answer 1

Given:

$m=15\rm\: kg$

$F=100\rm\: N$

$\mu_k=0.3$

$a-?$

The Newton's second law says

$$ma=F_{\rm net}$$

$$F_{\rm net}=F-F_f=F-\mu_k N=F-\mu_kmg$$

Hence, the acceleration of the system

$$a=\frac{F_{\rm net}}{m}=\frac{F}{m}-\mu_kg$$

$$a=\rm\frac{100\:N}{15\:kg}-0.3*9.8\: m/s^2=3.7\: m/s^2$$