MHT CET202521 Apr 2025Evening ShiftPhysicsLaws of MotionActual
A conveyor belt is moving with constant velocity (V). Sand is being dropped on the belt at the rate of M ~kg / s . The force necessary to keep the belt moving with a constant velocity V m / s will be
Options
- AMV 2 ~N
- B2 MV N
- CZero N
- DMV N
Correct answer
D. MV N
Step-by-step solution
The sand is deposited with zero initial horizontal velocity onto the belt moving at constant velocity V . The force needed to maintain constant belt velocity arises solely from accelerating each infinitesimal mass dm to speed V . The rate of mass deposition is M = dm dt , and the change in momentum for mass dm is dP = (dm) V . By Newton's second law, the required force equals the rate of momentum transfer: F = dP dt = V dm dt . Substituting the mass flow rate gives F = M V . The force necessary to maintain constant