Question

Two blocks with masses of 10 kg and 20 kg respectively are placed as in figure. Coefficient of friction between any two surfaces are 0.2 . Immediately after the system is released​

Answer 1

The tension in the blocks is T = 250 N and acceleration is a = 3 m/s^2

Explanation:

• Since block M1 will remain stationary as it is attached to the string.
• The block M2 will move downward.
• Thus the friction on M2 will act in upward direction.
• Both blocks are pressed by force N i.e., N=T cos(30∘)

For blocks M1

M1 g + μ (T cos 30∘) − T sin 30∘ = M1(0)   ---------(1)

( a=0 for M1 since attach to string )

For block M2

M2 g − (μN + μN) = M2a   ---------(2)

T = 250 N and a = 3 m/s^2

The tension in the blocks is T = 250 N and acceleration is a = 3 m/s^2