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A wheel starts from rest and reaches an angular speed of 6.0 rad/s while turning through 2.0 revolutions.  What is the average angular acceleration of the wheel?

If you do work on an object in one-third the usual time, your power output is

A woman is pushing a box along the ground. She is exerting a horizontal force of 156 N on the box. The box has a mass of 84.0 kg, . If the coefficient of kinetic friction between the box and the ground is 0.16, what is the acceleration of the box? ( g = 9.8 m/s2)

A 2.4-kg ball falling vertically hits the floor with a speed of 2.5 m/s and rebounds with a speed of 1.5 m/s. What is the magnitude of the impulse exerted on the ball by the floor?

An object moving in the +x axis experiences an acceleration of 2.0 m/s2. This means the object is:

Two equal mass balls (one red and the other blue) are dropped from the same height, and rebound off the floor.  The red ball rebounds to a higher position.  Which ball is subjected to the greater magnitude of impulse during its collision with the floor?

A large cannon is fired from ground level over level ground at an angle of 30◦ above the horizontal. The muzzle speed is 980m/s. Neglecting air resistance, the projectile will travel what horizontal distance before striking the ground?

A container of water is lifted vertically 3.0 m then returned to its original position.  If the total weight is 30 N, how much work was done?

A 10-kg mass is moving with a speed of 5.0 m/s.  How much work is required to stop the mass?

In order to catch a ball, a baseball player naturally moves his or her hand backward in the direction of the ball’s motion once the ball contacts the hand. This habit causes the force of impact on the players hand to be reduced in size principally because ___.