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Problems using energy conservation

 

  1. A mass of 2 kg is pushed against a horizontal spring on a frictionless table, compressing the spring 0.15m.  The spring has a force constant of 3000 N/m.  The spring is then released.  How fast does the mass move after it leaves the spring?

 

 

  1. Rework problem 1, assuming there is now friction, with mk = 0.2.

 

 

 

3.  Same spring, same compression, but this time the spring is oriented vertically.  How high does the mass go? 

 

 

 

 

 

4.  What does the initial height of a block have to be, in order to barely make it around a loop-the-loop of radius R?

 

 

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5.  An Atwood’s machine consists of two blocks, of mass m1 = 3 kg, and m2 = 4 kg.  The heavier block is initially in the air, a height h = 4m above the floor.  The blocks are released from rest. What is the speed of the blocks just before the heavy block hits the floor?

 

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