Question

A system of two blocks of masses m = 2 kg and M = 8 kg is placed on a smooth table as shown in the figure. The coefficient of static friction between two blocks is 0.5. The maximum horizontal force F that can be applied to the block of mass M so that the blocks move together will be

• A. 9.8 N
• B. 39.2 N
• C. 49 N
• D. 78.4 N

Answer 1

Answer: (C)

49 N

Answer 2

$∴ a_{max} = \mu g$

= $0.5 × 9.8 = 4.9 \;m/s^2$

$∴ F_{max} = (8 + 2) × 4.9$

$= 49 \;\text N$

Therefore, the correct option is (C): $49 \;\text N$