The circuit of a motor racing tracks 3 km in length. In a race, a car goes 25 times round the circuit in 30 minutes.
What is the average speed of the car?
A 75 km/hour
B 90km/hour
C 150km/hour
D 750 km/hour

The field between two charged parallel plates is kept constant. if the two plates are brought closer together, the potential difference between the two plates either a) decrease b) does not change c) increase?

Abaseball is thrown from the outfield toward the catcher. when the ball reaches its highest point, which statement is true? (a)its velocity is not zero, but its acceleration is zero. (b) its velocity and its acceleration are both zero. (c) its velocity is perpendicular to its acceleration. (d) its acceleration depends on the angle at which the ball was thrown. (e) none of the above statements are true.

Determine the time it takes for a satellite to orbit the earth in a circular "near-earth" orbit. the definition of "near-earth" orbit is one which is at a height above the surface of the earth which is small compared to the radius of the earth, so that you may take the acceleration due to gravity as essentially the same as that on the surface. does your result depend on the mass of the satellite?