Pseudo Force - NEET Physics Questions

Question 1:

A trolley of mass 8 kg is standing on a frictionless surface inside which an object of mass 2 kg is suspended. A constant force F starts acting on the trolley as a result of which the string stood at an angle of 37⁰ from the vertical (bob at rest relative to trolley) Then:

1. acceleration of the trolley is 40/3 m/sec.sec

2. force applied is 60 N

3. force applied is 75 N

4. force applied is 25 N

View Answer

Using concept of Pseudo force

a= g tanθ

⇒ a = g tan 37 = 10 ×3/4= 7.5 m/s^2

Using Equation of motion

⇒Fnet = 10×2.5 = 25 N

Question 2:

A man of weight W = Mg is standing on a lift which is moving upward with an acceleration a. If g is the acceleration due to gravity, the apparent weight of the man is

1. W (1 + a/g)

2. W (1 - a/g)

3. W

4. W(a+g)

View Answer

Taking lift as frame of reference, T = mg +ma = mg (1 +a/g) = W (1+ a/g)