Download First Semester Final Practice

.2 Physics First Semester Exam
Practice
These selected problems are to be used as practice. You should review your semester
outline for a more complete listing of the topics studied.
1. A scientific fact is……
a)
b)
c)
d)
e)
Something you believe is true because you know it.
An educated guess that has yet to be proven by experiment.
A synthesis of a collection of data that includes well-tested guesses.
Close agreement by competent observers of observations of the same phenomena.
A guess that has been tested over and over again and always found to be true.
2. These values were obtained as the mass of a bar of metal; 8 g, 11 g, 12 g, and 14 g. The
known mass is 11 g. The values are……
a) accurate
d) neither accurate nor precise
b) precise
c) both accurate and precise
3. In the process of delivering mail, a postal worker walks 161 m, due east from his truck. He
then turns around and walks 194 m, due west. What is the worker’s displacement relative to
his truck?
(a) 33 m, due west
(b) 33 m, due east
(c) 194 m, due west
(d) 252 m, due east
(e) 355 m, due west
The following two questions are concerned with the d-t graph below
D
An object is moving along a
straight line. The graph shows
the object’s position from the
starting point as a function of
time.
position (m)
40
30
20
B
10
A
0
1
C
2
3
4
time (s)
5
6
4. What was the instantaneous velocity of the object at t = 5.5 s?
(a) 0 m/s
(b) +10 m/s
(c) - 10 m/s
(d) +40 m/s
(e) - 40 m/s
E
5. The average velocity of the object from t = 0 s to t = 5 s is (Hint: d / t)
(a) +0 m/s
(b) +8 m/s
(c) +10 m/s
(d) +40 m/s
(e) - 40 m/s
The following two questions are concerned with the v-t graph below
An object is moving along a straight
line.
The graph shows the
object’s velocity as a function of
time.
velocity (m/s)
20
15
10
5
0
0
1
2
3
4
time (s)
5
6
6. What is the acceleration of the object in the interval from t = 2 s to t = 3 s?
(a) 0 m/s2
(b) +3.3 m/s2
(c) +10 m/s2
(d) +20 m/s2
(e) +30 m/s2
7. What is the displacement from t = 3 s to t = 5 s?
(a) 5 m
8.
(b) 10 m
(c) 15 m
(d) 20 m
(e) 30 m
A ball tossed vertically upward rises, reaches its highest point, and then falls back to its
starting point. During this time, the acceleration of the ball is always…
a) in the direction of motion
b) opposite its velocity
c) directed upward
d) directed downward
9. A ball is thrown horizontally from the top of a tall building and is in the air for a period of time
before it hits the ground. If it is again thrown horizontally but this time with twice the speed, it
will hit the ground..
a)
b)
c)
d)
four times as far from the base of the building
2 times as far from the base of the building
the same distance from the base of the building
at the same time as the first ball
Car One is traveling due north and Car Two is traveling
due east. After the collision shown, Car One rebounds
in the due south direction. Which of the numbered
arrows is the only one that can represent the final
direction of Car Two?
(a)
(b)
(c)
(d)
(e)
11.
(2)
(3)
(1)
(4)
(5)
Two
1
2
3
4
5
One
10.
If the radius of the Earth were one half what it is now, and the mass were the same, what
would be the value of g?
(a) 39.2 m/s2
(b) 19.6 m/s2
(c) 9.8 m/s2
(d) 4.9 m/s2
(e) 0 m/s2
12. A lunar month is about 28 days. If the moon were closer to Earth than it is now, the lunar
month would be..
(a) less than 28 days.
(b) more than 28 days.
(c) unchanged at 28 days.
13. In the centripetal force lab a student revolves a stopper (mass, m s) around themselves in a
horizontal circle of radius, r, with a string weighted by mass, m H. If the radius of the string
is increased but the stopper mass and hanging masses are kept the same, what will happen
to the speed of the revolving stopper?
(a) It will increase because the stopper has to change direction at a faster rate than before.
(b) It will increase because the stopper has to change direction at a slower rate than before.
(c) It will increase because the stopper has to change direction at the same rate as before.
(d) It will decrease because the stopper has to change direction at a faster rate than before.
(e) It will decrease because the stopper has to change direction at a slower rate than before.
(f) It will decrease because the stopper has to change direction at the same rate as before.
14. An amusement park ride sometimes called ‘the fly’ is a large cylinder which can rotate. A
person stands against the wall, and after the cylinder is rotating at a certain rate the floor
drops away. The person remains ‘stuck’ in position against the wall - like a fly.
Which one of the following is the correct free-body force diagram showing all the forces acting on
the person when the person is in the position shown above?
15. What is providing the centripetal force that keeps the person moving in a
circle?
(a) Friction
(b) Gravity
(c) Normal
(d) Centrifugal
16. If the ride was twice the radius but the person was moving at the same speed
what would happen to the centripetal force exerted on the person?
A.
B.
C.
D.
E.
It would increase to twice its previous amount
It would decrease to half its previous amount
It would increase to √2 its previous amount
It would decrease to √2 its previous amount
It wouldn’t change
17.
A cannonball shot from a long-barrel cannon travels faster than one shot from a shortbarrel cannon because the cannonball receives a greater…
(a) force
(b) impulse
18.
(c) both (a) and (b)
(d) neither (a) and (b)
A rocket is fired vertically. At its highest point, it explodes. Which one of the following
describes what happens to its total momentum and total kinetic energy as a result of
the explosion?
Total momentum
Total kinetic energy
A.
unchanged
increased
B.
unchanged
unchanged
C.
increased
increased
D.
increased
unchanged
19. A car and a truck traveling with equal speeds in opposite directions collide
head-on. The truck is more massive than the car.
How will the momentum changes of the vehicles compare in the collision?
A.
B.
C
D.
The car will have the greater momentum change.
The truck will have the greater momentum change.
The car and truck will have equal but opposite momentum changes.
One cannot compare momentum changes for an inelastic collision such as this.
20. Two cars travelling at the same speed slam on their breaks and slide to a
stop. If Car B has twice the mass of Car A the stopping distance of Car B will
be…
A.
B.
C.
D.
Half as much as Car A because it has twice the friction force.
The same as Car A because speed is the deciding factor.
Twice as much as Car A because it has twice the inertia.
Four times as much as Car A because kinetic energy depends on the square of the
mass.
Answers
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
D
A
A
E
B
A
E
D
D
D
A
A
C
B
C
B
B
A
C
B