A race car moves along a circular track at a speed of 0.512 m/s. If the car's centripetal acceleration is 15.4 m/s2, what is the distance between the car and the center of the track?

The radius is    

Explanation:

From the question we are told that

      The speed at which the race car moves is

       The centripetal acceleration is  

Generally the centripetal acceleration is mathematically represented as

=>        

=>        

air exerts forces on falling objects near earth’s surface.

explanation:

the term 'free falls' refer to object that are falling towards the earth, in a situation in which gravity is the only force acting on the object.

for an object in free fall, the acceleration is constant (g, the gravitational acceleration), and so the velocity of the object constantly increases.

for objects near earth's surface, there is always another force acting on the object: the resistance due to the air. this force is opposed to the direction of fall of the object, and it is proportional to the velocity of the object, so as the object falls down, this force increases up to a point when it balances the force of gravity, and the object continues its motion at constant velocity (called terminal velocity). since in this case gravity is not the only force acting on the object, we are not in a situation of free fall.