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An object weighs 10-Newton  and moves to the left at 1 m/s. Its kinetic energy is approximately ____ Joules.

A sledge (including load) weighs 5000 N. It is pulled on level snow by a dog team exerting a horizontal force on it. The coefficient of kinetic friction between sledge and snow is 0.05. How much work is done by the dog team pulling the sledge 1000m at constant speed?

If the net work done on an object is positive, then the object’s kinetic energy  

A diver who weighs 500 N steps off a diving board that is 10 m above the water. The diver hits the water with kinetic energy of

An ice skater has a moment of inertia of 5.0 kg∙m2 when her arms are outstretched.  At this time she is spinning at 3.0 revolutions per second (rps).  If she pulls in her arms and decreases her moment of inertia to 2.0 kg∙m2, how fast will she be spinning?

On a balanced seesaw, a girl three times as heavy as her partner sits

A bicycle wheel rotates uniformly through 2.0 revolutions in 4.0 s.  What is the frequency of the wheel’s rotation?

Action-reaction forces are

A 2000-kg car, traveling to the right at 30 m/s, collides with a brick wall and comes to rest in 0.20 s.  What is the average force the car exerts on the wall?

A 2-kg object is moving at 3m/s. A 4-N force is applied in the direction of motion and then removed after the object has traveled an additional 5m. The velocity  after the object travels 5 m is: