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

A driver, traveling at 22 m/s, slows down her 2000 kg car to stop for a red light.  What work is done by the friction force against the wheels?

Neglecting the effect of air resistance a stone dropped off a 175-m high building lands on the ground in:

A 7.6 kg chair is pushed across a frictionless floor with a force of 42 N that is applied at an angle of 22° downward from the horizontal. What is the magnitude of the acceleration of the chair?

Two spacemen are floating together with zero speed in a gravity-free region of space. The massof spaceman A is 120 kg and that of spaceman B is 90 kg. Spaceman A pushes B away from him with B attaining a final speed of 0.5m/s. The final recoil speed of A is:

A meter stick on a horizontal frictionless table top is pivoted at the 80-cm mark. It is initially at rest. A horizontal force F1 is applied perpendicularly to the end of the stick at 0 cm, as shown. A second horizontal force F2 (not shown) is applied at the 100-cm end of the stick. If the stick does not rotate:

A bicycle wheel rotates uniformly through 2.0 revolutions in 4.0 s.  What is the linear speed of a point 0.10 m from the center of the wheel?

Vector  V is 8.5 units long and points at  600 to the positive x axis.  What are the x and y components of this vector?

  A football field is 120 yd long and 50 yd wide. What is the area of the football field, in m 2, if 1 yd = 91.44 cm?  

A man pulls a sled along a rough horizontal surface by applying a constant force F at an angle θ above the horizontal. In pulling the sled a horizontal distance d, the work done by the man is: