NTA Abhyas JEE Main2020PhysicsRotational MotionPractice
As shown in the figure, wheel A of radius r A = 10 c m is coupled by a belt B to the wheel C of radius r C = 25 c m . The angular speed of wheel A is increased from rest at a constant rate of 1.6 r a d s - 2 . Time after which wheel C reaches a rotational speed of 100 r p m , assuming the belt does not slip, is nearly
Options
- A4 s
- B8 s
- C12 s
- D16 s
Correct answer
D. 16 s
Step-by-step solution
a t = α A   r A = α C r C α C =   α A   r A r C =   1.6 × 10 25 = 0.64   rad   s - 2 t = ω C α C = 100 × 2 π 60 0 .64 = 16.35  s