A trolley of mass 300 kg carrying a sandbag of 25 kg is moving uniformly with a speed of 27 km/h on a frictionless track. After a while, sand starts leaking out of a hole on the floor of the trolley at the rate of 0.05 kg s–1. What is the speed of the trolley after the entire sand bag is empty? | Learn NCERT solution | Education portal Class 11 Physics | Study online Unit-6 Work, Energy And Power





Q.19:- A trolley of mass 300 kg carrying a sandbag of 25 kg is moving uniformly with a speed of 27 km/h on a frictionless track. After a while, sand starts leaking out of a hole on the floor of the trolley at the rate of 0.05 kg s–1. What is the speed of the trolley after the entire sand bag is empty?

 

Answer:-
As the trolley carrying the sand bag is moving uniformly, therefore, external force on the system = 0.
When the sand leaks out, it does not lead to the application of any external force on the trolley. Hence, the speed of the trolley shall not change.