Unit 1. Newtonian Mechanics
I. Kinematics
1.
A person drives a car in a straight line along a street. The speed of the car as a function of time
t
for a three second duration is shown in the above graph. What is the car's average acceleration over these three seconds?
0 m/s
2
0.3 m/s
2
1.0 m/s
2
2.0 m/s
2
3.0 m/s
2
2.
An object of mass
m
dropped from an airplane experiences an air resistance force
F = kv
2
, where
k
is an experimentally determined constant. In terms of given variables and fundamental constants, what is the object's terminal velocity?
3.
A 7.0 kg bowling ball is dropped off the roof of a building, 10 m above the ground. Taking the effects of air resistance into account, about how much time elapses before the ball hits the ground?
0.7 s
1.0 s
1.4 s
2.2 s
2.8 s
4.
A car drives 600 km to the west in 2 hours. Next, the car drives 800 km north in 3 hours. What is the car's average velocity for the entire trip?
650 km/hr, 53° north of west
400 km/hr, 53° north of west
200 km/hr, 53° north of west
700 km/hr, 53° north of west
750 km/hr, 53° north of west
5.
A particle moves according to the equation of motion
v
= 3 + 5
t
, where
v
represents velocity in m/s, and
t
represents time in seconds. How far does the object move between
t
= 0 and
t
= 2 s?
3.0 m
13.0 m
15.5 m
12.5 m
9.0 m
6.
A particle's velocity as a function of time is given by
v
(
t
) = v
0
+
zt
2
, where
z
is a positive constant. Which of the following is a correct sketch of the particle's acceleration as a function of time?
A
B
C
D
E
7.
Jim and Sara stand at the top of a high cliff. Jim throws a heavy ball straight up with an initial speed of 5 m/s. Simultaneously, Sara throws an identical ball with the same initial speed, but she throws the ball at some angle above the horizontal. Whose ball reaches the peak of its flight first?
Jim's
Sara's
Both reach the peak at the same time.
The answer depends on the height of the cliff.
The answer depends on the angle of Sara's throw.
Questions 8 and 9 refer to the following statement:
A cart moves forward at speed 6.0 m/s on a frictionless surface. It fires a ball straight up (relative to the cart) with a speed of 3.0 m/s.
8.
How far has the cart traveled before the ball returns to its launch height?
10.0 m
6.0 m
3.6 m
1.5 m
18.0 m
9.
When the ball returns to launch height, what is the displacement of the ball relative to the cart? Consider the forward direction to be positive.
+ 10.0 m
0 m
- 10.0 m
- 6.0 m
- 3.0 m
10.
A ball is projected with speed v at an angle θ above the horizontal. How much time elapses before it lands on a level surface?
