1. Which of the following fundamental forces only exerts forces of attraction, never repulsion?
a. gravitational
d. strong nuclear
b. electromagnetic
e. gravitational and electromagnetic
c. weak nuclear
2. The net force acting on the stone is supplied by friction.
3.
b.
c.
d.
e.
The applied force is just equal to the frictional force.
The stone is moving with uniform motion.
The frictional force is greater than the applied force which is acting.
The net force is zero.
3. Two identical arrows, A and B, are fired with different bows. The bow that fires arrow A exerts twice the
average force as the bow that fires arrow B. Compare the accelerations of the two arrows.
a. Arrow B will have twice the acceleration of arrow A.
b. Arrow A will have twice the acceleration of arrow B.
c. Arrow A and arrow B will have the same acceleration.
d. Arrow B will have four times the acceleration of arrow A.
e. Arrow A will have four times the acceleration of arrow B.
4. A 2.5  103 kg car is travelling due west at 30 m/s when the brakes are applied, exerting a force of 5.0 
103 N [E]. What is the car's acceleration due to the braking?
5. The action and reaction forces of Newton's third law
a. act on the same object
b. act as a pair of forces that are "balanced"
c. make the net force zero because they are equal in strength and opposite in direction
d. act on two different objects
e. cancel each other out like Fg and FN
6. Two children wrestle over a toy of mass 1.5 kg. The boy pulls with a force of 6.0 N [W] while the girl pulls
with a force of 8.0 N [E]. The toy slides with an acceleration of 1.0 m/s2.
(a) Draw a free-body diagram of the situation.
(b) Determine the value of the frictional force acting on the toy.
7. A 2.0-kg object is sliding across a smooth surface at 4.0 m/s when it collides with a stationary 3.0-kg object.
The collision lasts for 0.80 s after which the smaller object has slowed to a speed of 1.0 m/s. Using the
diagram below,
(a) Determine the acceleration of the smaller object.
(b) Determine the force that the smaller object exerts on the larger one.
(c) Determine the speed of the larger object immediately following the collision.
8. A stationary elevator and its contents have a combined mass of 2000 kg. The elevator is suspended by a single
cable. (Assume 3 significant digits.)
(a) Draw a free-body diagram of the elevator and calculate the values of all the forces that are acting on it
when at rest.
(b) If the elevator is ascending at a speed of 4.0 m/s, what are the values of the forces acting at this point?
(c) If the elevator is descending at 4.0 m/s2, what are the values of all the forces acting at this point?