Physics Prelecture Video: Work and Kinetic Energy

A motorcycle drives up a steeply inclined ramp. The work done on the motorcycle by the Earth's gravitational force is ____.

Negative -When an object's displacement has a component in a direction opposite that of a given force, that force does negative work on the object

During a certain time interval, the net work done on an object is zero joules. We can be certain that ____.

The object's final speed was the same as its initial speed -When the net work done on an object is zero, there is no overall change in the object's kinetic energy

Two identical cars are driving in opposite directions at the same speed. Their kinetic energies have ____.

The same magnitude and sign -The kinetic energy of a moving object is always positive, regardless of the direction it is moving in, or the coordinate system used