A trolley of mass 300 ks carrying a sand bag of 25 kg is moving uniformly with a speed of `27km//h` on a frictionless track. After a while, sand starts leaking out of a hole on the trolley's floor at the rate of `0.05kgs^(-1)`. What is the speed of the trolley after the entire sand bag is empty ?

Explanation

As the trolley is moving with a uniform sped . Therefore , no external force is acting on the trolley . When the sand leaks out , no external force is acting on the system Hence the speed of the trolley remains unchanged even after the sand bad becomes empty .