Physics 160 - MC Practise for Test 1
1. A pole-vaulter clears a crossbar set at 16 ft 5 in. How high is this
in centimeters?
Correct Answer:
500 cm
2. A runner finishes a marathon in 2 hr 58 min and 17 s. How many
seconds did it take him to run the marathon?
Correct Answer:
10,697 s
3. A weightlifter lifts a 108 kg barbell. How much does this barbell
weigh in pounds?
Correct Answer:
238 lb
4. The study of the time and space characteristics of movement is
called
a. kinetics
b. statics
c. dynamics
*d. kinematics
e. anthropometrics
5. The division of mechanics that is most applicable to the study of
the human body in sport and exercise is called
a. relatively deformable mechanics
b. deformable-body mechanics
c. quantum mechanics
d. relativistic mechanics
*e. rigid-body mechanics
6. The study of systems with no change in their state of motion is
called
a. dynamics
*b. statics
c. kinetics
d. kinematics
e. anthropometrics
7. The process of determining each of the forces that combine to make
up a resultant force is called
a. force composition
*b. force resolution
c. scalar composition
d. scalar resolution
e. trigonometry
8. The force that acts perpendicular to an object in contact with a
surface is called
a. friction force
*b. normal contact force
c. internal force
d. colinear force
e. resolved force
9. The force that acts parallel to an object in contact with a surface
is called
*a. friction force
b. normal contact force
c. internal force
d. colinear force
e. resolved force
10. As the normal contact force increases, what happens to the friction
force?
*a. It increases.
b. It decreases.
c. It remains constant.
d. It disappears.
e. This depends on the weight of the object.
11. If a normal force of 500 N is acting on two surfaces in contact
with a coefficient of friction equal to 0.50, what would be the maximum
force of static friction?
a. 1000 N
b. 500 N
*c. 250 N
d. 0 N
e. need more information to calculate
12. When drawing a sketch of a dancer pushing off in a jump, which of
the following is NOT a force to be considered?
a. the dancer's weight
b. the push of the floor on the dancer's foot
*c. the speed of the dancer across the floor
d. the friction of the floor on the dancer's shoe
13. How much does a 115 kg barbell weigh in newtons?
Correct Answer:
1128 newtons
14. The coefficient of dynamic friction between the grass and a 200 kg
football blocking sled is 0.20. If a 100 kg football player only pushes
horizontally against the sled, how large must the horizontal force be
to keep the sled moving at constant velocity?
a. 40 N
b. 20 N
*c. 392 N
d. 40 kg
e. 589 N
15. A 90 kg weightlifter exerts a 1000 N force upward against a 50 kg
barbell. How large is the net vertical force acting on the barbell?
a. 1050 N
*b. 510 N
c. 1050 kg
d. 950 kg
e. 1490 N
16. A 100 kg shot-putter pushes forward and upward on a 4 kg shot with
a force of 1000 N. This force acts at an angle of 60° above horizontal.
How much of this 1000 N force acts in the forward direction (i.e., what
is the horizontal component of this 1000 N force)?
*a. 500 N
b. 866 N
c. 1000 N
d. 500 kg
e. 160 kg
17. To fully define a vector quantity, you must specify
a. length and magnitude
b. length and area
c. area and direction
*d. direction and magnitude
e. none of the above
18. The maximum limiting friction between a shoe and the track has been
calculated to be 500 N. If a motive force of 560 N is applied to the
shoe when it is at rest on the track, the magnitude of the friction
present will be
a. 60 N
b. 500 N
c. 560 N
d. 1060 N
*e. need more information to calculate
19. Which of the following statements is true of the amount of
horizontal force required to start in motion an object sitting on a
horizontal surface?
a. It must be greater than the coefficient of kinetic friction.
b. It must be greater than the coefficient of static friction.
c. It must be greater than the maximum kinetic friction force.
*d. It must be greater than the maximum static friction force.
e. none of the above
20. Which of the following, when present, is NOT an external force
applied to a runner?
a. gravitational force
b. weight
c. friction
*d. muscle force
e. All of the above are external forces.