Explain why the friction force between two surfaces increases if the force is pushing the surfaces together increases .

the friction is becouse of the microscopic bumps between 2 surfaces and matters,it's a contact force.so with pushing them tge contacts between the bumps increases so the force will increase to

Answertraveling around a circular trackexplanation"traveling around a circular track" is the best answer as you could be traveling around a circular track at a constant speed. your velocity would therefore have the same magnitude but will always be constantly direction. since acceleration is the rate of change of velocity, the rate of change will only involve the direction of velocity and not the magnitude.wrong choices: "an object at rest" does not accelerate at all"increasing speed while traveling around a curve" means that the acceleration will not be constant due to only change in direction; it will be constant due to both magnitude and direction"an object in free fall" does not necessarily change direction