Question

Two blocks of masses 5kg and 2kg (see fig.) are initially at rest on the floor. They are connected by a light string, passing over a light frictionless pulley. An upward force F is applied on the pulley and maintained constant. Calculate the acceleration a₁ and a₂ of the 5kg and 2kg masses, respectively, when F is 110N (g = 10ms^-2).

 

(A) a₁ = 1ms^-2, a₂ = 17.5ms^-2 

(B) a₁ = 1ms^-2, a₂ = 0 

(C) a₁ = 2ms^-2, a₂ = 17.5ms^-2 

(D) a₁ = 2ms^-2, a₂ = 0

Answer 1

(A) a₁ = 1ms^-2, a₂ = 17.5ms^-2 

When F = 110 N 

110 - 2T = 0 

T = 55 N 

Thus both the weights will be lifted up 

55 -50 = 5 * a₁ 

a₁ = 1 m/sec² 

55 -20 = 2 * a₂ 

a₂ = 17.5 m/sec²

Comments

Can you post the complete soln