A small car of mass M travels along a straight, horizontal track. As suggested in the figure, the track then bends into a vertical circle of radius R.
-Which one of the following expressions determines the minimum speed that the car must have at the top of the track if it is to remain in contact with the track?

Question

A small car of mass M travels along a straight, horizontal track. As suggested in the figure, the track then bends into a vertical circle of radius R.

-Which one of the following expressions determines the minimum speed that the car must have at the top of the track if it is to remain in contact with the track?

Quizplus · Accepted Answer

At the top of the track, the centripetal force required to keep the car in contact with the track is provided by the gravitational force. Thus, mv²/R = mg, leading to v² = gR.

A Small Car of Mass M Travels Along a Straight