Q.

A wedge Y with mass of 10 kg and all frictionless surfaces and the inclined surface making 37° with horizontal. A block X with mass 2 kg is placed at the highest point of the wedge as shown in figure is at rest. At t=0 wedge (Y) is pulled toward right with constant force (f) of 24 N. Taking the block X at rest at t=0, the time taken by it to slide down 8.8 m on the slope, while Y is on the move, is _________ s.

(Take tan(37°)=34 and g=10 m/s2)                                  [2026]

1 2  
2 4  
3 2  
4 22  

Ans.

(1)

Apply NLM on system along x direction.

10a+2[bcos37°+a]=24

60a+8b=120                              ...(i)

NLM on block along inclined plane

2×10sin37°=2[b+acos37°]

⇒4a+5b=30                              ...(ii)

from (i) and (ii)

60[30-5b4]+8b=120

⇒b=33067 ms-2

⇒t=2×8.8×67330≈2 sec