question_answer

Three blocks of masses 4 kg, 2 kg, 1 kg respectively are in contact on a frictionless table as shown in the figure. If a force of 14 N is applied on the 4 kg block, the contact force between the 4 kg and the 2 kg block will be

A)  2N               

B)  6N

C)  8N               

D)  14N

Correct Answer: B

Solution :

 We know that, F = ma \[a=\frac{F}{m}=\frac{14}{7}=2\,m{{s}^{-2}}\] Hence, from the figure \[14-N=4a\] \[14-N=8\] \[N=6N\]