Physics 111 Final Exam Questions and Correct
Answers
A frog is resting on a sloped tree branch. The frog has the weight of 15 N. What can you
say about the magnitude of the normal force on the frog?
The normal force is less than 15 N
A box with a weight of 100 N is at rest. It is then pulled by a 55N force. Will the box
move?
Yes
All 3 50 kg blocks are at rest. The tension in rope 2 is:
Equal to the tension in rope 1
The fan blade is slowing down. What are the sings of w and a? (turning clockwise)
w is negative and a is positive
A 2kg ball moving east at 3.0 m/s collides and sticks to a 4 kg ball moving north at 2.0
m/s. What is the magnitude of the momentum after the collision?
10 kgm/s
Why are doorknobs placed at the edges of doors rather than in the center?
to increase the lever arm
A 15 kg child is sitting on a teeter totter, 1.5 m away from the pivot point. What is the
minimum distance such that a 220 N force will life the child off of the ground?
1.0 m
Answers
A frog is resting on a sloped tree branch. The frog has the weight of 15 N. What can you
say about the magnitude of the normal force on the frog?
The normal force is less than 15 N
A box with a weight of 100 N is at rest. It is then pulled by a 55N force. Will the box
move?
Yes
All 3 50 kg blocks are at rest. The tension in rope 2 is:
Equal to the tension in rope 1
The fan blade is slowing down. What are the sings of w and a? (turning clockwise)
w is negative and a is positive
A 2kg ball moving east at 3.0 m/s collides and sticks to a 4 kg ball moving north at 2.0
m/s. What is the magnitude of the momentum after the collision?
10 kgm/s
Why are doorknobs placed at the edges of doors rather than in the center?
to increase the lever arm
A 15 kg child is sitting on a teeter totter, 1.5 m away from the pivot point. What is the
minimum distance such that a 220 N force will life the child off of the ground?
1.0 m
