A box on a horizontal surface (w/ friction) is pulled at a constant rate by a rope that makes an angle up from the horizontal. If the vertical component of the force is not large enough to lift the box off the table, what is the net force, acceleration, velocity, position as a function of time?

 

 

A box on a horizontal surface (w/ friction) is pulled at a constant rate by a rope that makes an angle up from the horizontal for a while and then the rope breaks. If the vertical component of the force was not large enough to lift the box off the table, how long will it take for the box to come to rest?

A box is sliding to the right on the floor of an elevator that is moving upwards and slowing down. Sketch a FBD of the box during the time it slides to rest, being careful to scale the vectors relative to each other.

A box is sliding on the floor of an elevator that is moving upwards and slowing down. How does the time it takes the box to come to rest compare to if the elevator was in equilibrium?

 

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What is the direction of the friction on the block?

 

 

  1. Towards the right
  2. Downward
  3. Upward
  4. Not enough information

What is the direction of the friction on the block from the hand?

 

  1. Towards the right
  2. Towards the left
  3. Not enough information

 

What is the direction of the velocity of the block?

 

  1. Towards the right
  2. Towards the left
  3. Not enough information

 

 

 

The half-kg-block on the hand undergoes an acceleration with a magnitude of 2 m/s2 and doesn't slip relative to the hand. What is the frictional force on the block?

 

 

 

 

 

 

 

If wind imparts a 1/2 N force in the opposite direction of the block's acceleration, what is the frictional force on the block?

 

 

 

 

 

 

If the coefficient of static friction between the block and the hand is 0.5, what is the maximum acceleration, in m/s2, the block can attain without sliding relative to the hand?

 

Starting from rest the hand increases the rate of its acceleration. Eventually the block begins to slide relative to the hand.

Sketch a plot of the frictional force on the block as a function of time.