Physlet Illustration: Work Done Pulling a Block at an Angle

 

 

Interactive Help
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F= Newtons  q = ° 
A 20-kg block is being pulled by a rope across a frictionless floor, as shown. The rope makes an angle q with the horizontal. The velocity is given in m/s, and the distance grid is in meters. Adjust the angle (q < 90°) and/or the magnitude of the pulling force (F < 200 N), and monitor the work done on the block in the accompanying graph. Can you verify that the work displayed on the graph is calculated correctly? 

Hints

  1. Choose any time to pause the animation.
  2. How far has the block moved in this time?
  3. How much work has been done on the block by this time?
  4. What is the block's speed at this time?
  5. What is its kinetic energy?
  6. What can you conclude about the relationship between the work done on the block and its kinetic  energy?

Reference

See Walker, Sections 7-1 and 7-2

Illustration written by Steve Mellema and Chuck Niederriter