Question

Can somebody please help me?!

According to Newton’s first law, if no force acts on an object, it will just continue moving. Explain in terms of Newton’s first law why a car engine must exert a force between the car and the road to drive at a constant speed on a straight and level road.

Answer 1

I think that the explanation is this:
during motion of your car there is a friction between the wheels of the car and the road, and between your car and the air surrounding the same car. Those friction forces due are opposite to the motion of a car, so if we want that the car will move in with uniform rectilinear motion, we have to apply to the car a force opposite to the above friction forces in order to balance such friction forces.

Answer 2

Thank you!

Answer 3

Thank you!