A body of weight ω₁ is suspended from the ceiling of a room through a chain of weight ω₂. The ceiling pulls the chain by a force

When a train starts, the head of a standing passenger seems to be pushed backward. Analyze the situation from the ground frame. Does it really go backward? Coming back to the train frame, how do you explain the backward movement of the head on the basis of Newton’s laws?

A plumb bob is hung from the ceiling of a train compartment. If the train moves with an acceleration ‘a’ along a straight horizontal track, the string supporting the bob makes an angle tan^-1 (a/g) with the normal to the ceiling. Suppose the train moves on an inclined straight track with uniform velocity. If the angle of incline is tan^-1 (a/g). the string again makes the same angle with the normal to the ceiling. Can a person sitting inside the compartment tell by looking at the plumb line whether the train is accelerated on a horizontal straight track or it is going on an incline? If yes, how? If no, suggest a method to do so.

When a horse pulls a cart, the force that helps the horse to move forward is the force exerted by

A car accelerates on a horizontal road due to the force exerted by