Question

Two blocks are in contact on a frictionless table one has a mass m and the other 2 m as shown in figure. Force F is applied on mass 2m then system moves towards right. Now the same force F is applied on m. The ratio of force of contact between the two blocks will be in the two cases respectively.

• A. 1 : 1
• B. 1 : 2
• C. 1 : 3
• D. 1 : 4

Answer 1

The correct option is B

1 : 2

When the force is applied on mass 2m contact force $f_1=\frac{m}{m+2m}g=\frac{g}{3}$

When the force is applied on mass m contact force $f_2=\frac{2m}{m+2m}g=\frac{2}{3}g$

Ratio of contact forces $\frac{f_1}{f_2}=\frac{1}{2}$