Question

A heavy box of mass 50 kg is moving on a horizontal surface. If co-efficient of kinetic friction between the box and horizontal surface is 0.3 then force of kinetic friction is : 

(1) 14.7 N 

(2) 147 N 

(3) 1.47 N 

(4) 1470 N

Answer 1

Correct option is : (2) 147 N

\(\mathrm{F}_{\mathrm{k}}=\mu_{\mathrm{k}} \mathrm{N}=0.3 \times 50 \times 9.8=147 \mathrm{~N} \)