Physics question

Question

Science question: If the car is started on a zero friction surface and zero air resistance but force of gravity acting upon it, Will it continue to travel at a constant speed even when engine is switched off??

Answer 1

The wording of the problem is a bit strange, is this exactly how the problem was stated?

 

If there were zero friction the car would not be able to start moving in the first place. The tires require friction in order to roll. Imagine trying to accelerate on ice for instance, you could get the wheels spinning, yet the car wouldn't take off as fast as it would on pavement. This is due to low friction. If we were on a surface with perfectly zero friction, then we're not going anywhere. The car would not accelerate.

Answer 2

Newton's First Law:

 

An object in a state of uniform motion will remain in that state of motion unless an external force is applied to it

 

Surface friction and air resistance are external forces but are zero in your problem.  So what does Newton's Law tell you?

Answer 3

This question cannot be answered as other info is missing. Is it on a level surface, or is it on a slope? On the level surface, the effect of gravity is zero, and the car would not move. On a slope, even a slight slope, the car would accelerate (in the absence of friction and air resistance) because the net force is the component of the weight parallel to the slope.