Question

Explain the following :
When a corridor  train suddenly starts , the sliding doors of some compartments may open .

Answer 1

The frame of the sliding door being in contact with the floor of the train also comes in motion on start of the train, but the sliding door remains in its position due to inertia. Thus, the frame moves ahead with the train, while the door slides opposite to the direction of motion of the train. Thus, the door may shut or open accordingly.