2. a 200.0-kg bear grasping a vertical tree slides down at constant velocity. what is the friction force between the tree and the bear?

1960 N

Explanation:

The bear is sliding down at constant velocity: this means that its acceleration is zero, so the net force is also zero, according to Newton's second law:

There are two forces acting on the bear: its weight W, pulling downward, and the frictional force Ff, pulling upward. Therefore, the net force is given by the difference between the two forces:

From the previous equation, we find that the frictional force is equal to the weight of the bear:

not moving. pos accel,