Browse Questions

# Consider a car moving west along a highway with a constant velocity of 65 km per hour. What happens when the driver takes his foot off the accelerator pedal?

Toolbox:
• Newton's first law states that when viewed in an inertial reference frame, an object either remains at rest or continues to move at a constant velocity, unless acted upon by an external force.
Answer: Car slows down and comes to a stop.
The car slows down, and it comes to rest because of friction. In the absence of friction, he car should remain at a velocity of 65 mph, as long as the forces are balanced, according to Newton's first law.