PhysicsLAB: Freebody Diagrams #3

Worksheet
Freebody Diagrams #3

Refer to the following information for the next four questions.


A	B	C

Which freebody diagram could represent a block sitting on the floor of an elevator that is in a state of equilibrium: that is,

either at rest, or

ascending/descending at a constant velocity?

ABC

Which freebody diagram shown above would match the equation

indicating that the block is sitting on the floor of an elevator that is accelerating upward?

ABCcannot be determined without more information

What would be the apparent weight of the block (or net force normal), expressed in terms of mg (its true weight), while the elevator is accelerating upwards if the elevator starts from rest and takes 0.6 meters to attain its final "cruising" velocity of 2 m/sec?

0.34 mg0.48 mg1.00 mg1.34 mg1.48 mg

According to the graph shown above, does the elevator lose speed as it slows down to stop on the next floor faster or slower than it gained speed when it left the lower floor?

fasterslowerat the same rate

Refer to the following information for the next two questions.


A	B	C

These three freebody diagrams illustrate that the value of the normal is affected by the direction of the applied force. In which diagram does the normal equal the object's weight?

ABCcannot be determined without more information

Which of the following expressions correctly represents the value of the normal in diagram C?

Refer to the following information for the next question.

This block is being pushed at a constant velocity towards the right along a rough surface.

Which expression correctly represents the value of the coefficient of friction between the block and the surface?

Refer to the following information for the next three questions.


A	B	C

If the block in diagram A were to be moving up the incline at a constant velocity, the magnitude of the kinetic friction present would equal?

If the block in diagram B were to move down the incline at a constant velocity, the coefficient of the kinetic friction present would equal?

Which of the following expressions correctly represents the value of the normal in diagram C?