Question

Newton's 2nd law says that if an object is moving in a straight line at a constant speed, the net externalforce on the object is 0. When you tell your friend about this he says that can't be possibly be true because when he drives in a straight line at a constant speed, he must keep his foot on the gas to do so. Therefore, he says your physics teacher is wrong. To move in a straight line at a constant speed requires a constant netzero net force. in other words, for straight line motion at a constant speed net force cannot equal 0. what is your friend's flaw in his argument?

Answer 1

There are plenty of opposing forces on the car. For example, there is drag on the car from the air and the friction between all of the moving parts in the car.