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Work, Energy, and Power — Physics STD 11 Science — Question

Gujarat BoardEnglish MediumSTD 11 SciencePhysicsWork, Energy, and Power3 Marks
Question
A trolley of mass $300kg$ carrying a sandbag of $25kg$ 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 floor of the trolley at the rate of $0.05 kgs^{-1}$. 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.

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