Forces
Choose the correct answer for each question.
1
When you are standing still on both feet, each foot feels ________ of your normal weight.
half
less than half
more than half
depends on the size of your feet
2
When you push yourself up from a sitting position on the floor using only your feet, each foot feels _______ of your normal weight.
half
less than half
more than half
(this can't be done)
3
A 160 LB man stands in an elevator on a scale. When the elevator is rising at a constant speed of 2 ft/s what will the scale read?
164 LB
160 LB
180 LB
170 LB
4
A 160 LB man stands in an elevator on a scale. When the elevator is rising at a constant acceleration of 4 ft/s^2 the scale will read
160 LB
164 LB
180 LB
140 LB
5
A 160 LB man stands in an elevator on a scale. When the elevator is falling at a constant acceleration of 4 ft/s^2 down what will the scale read? A. 160 LB B. 164 LB C. 180 LB D. 140 LB
160 LB
164 LB
180 LB
140 LB
6
A ball is dropped. According to Newton's Third Law, the action force is the pull of the earth on the ball and the reaction force is
the air resistance acting on the ball
the pull of the ball on the earth
the force the ground exerts on the ball when it hits
nonexistent in this case
7
Mrs. Woolard lifts a box containing 20 kg of books at a constant speed. When she applies the same force to a similar box containing only 5 kg of books, the acceleration produced in m/s^2 is
29.4
19.6
9.8
4.9
8
A block of mass 2.0 kg slides down a smooth incline which makes an angle of 30* with the horizontal. The blocks starts from rest and slides the length of the very smooth incline which is 4.0 m long. The speed of the block at the bottom is
2.9 m/s
8.8 m/s
4.4 m/s
6.3 m/s
9
Acceleration is always in the direction of
Of the displacement
Of the initial velocity
Of the final velocity
Of the net force
10
In the diagram, the two weights are at rest. What would be the reading of the scale?
6 N
12 N
36 N
0 N