Q.
Maximum acceleration of the train in which a 50kg box lying on its floor will remain stationary (Given : Co-efficient of static friction between the box and the train’s floor is 0.3 and g=10ms−2)
Key Idea Motion is possible when ma≥μmg.
The maximum static frictional force =μsmg should be equal to force F=ma ∴F=ma=μsmg ⇒a=μsg
Here, μs=0.3.g=10ms−2 a=(0.3)×10 ⇒a=3ms−2