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

Answer: (B)

1 : 2

Answer 2

When the force is applied on mass 2m contact force $f _ { 1 } = \frac { m } { m + 2 m } g = \frac { g } { 3 }$

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

Ratio of contact forces $\frac { f _ { 1 } } { f _ { 2 } } = \frac { 1 } { 2 }$