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First Semester Exam Study Guide - Page 1
PHYSICS
1st Semester Exam – REVIEW
Name: _____________________________________________ Date: __________ Period: _________
Unit 1 - Accelerated motion
Vf = Vi + a ∆t
Vf =
√ Vi2
+ 2 a ∆s
∆s = Vi ∆t + ½ a (∆t)2
d=rt
F = ma
1. If an object is dropped and falls for 4 seconds its velocity will be
a. -78.4 m/sec
b. -0.41 m/sec
c. -39.2 m/sec
d. -2.45 m/sec
e. -19.6 m/sec
2. If an object is dropped and falls for 4 seconds the distance it falls will be
a. -78.4 m
b. -0.41 m
c. -39.2 m
d. -2.45 m
e.-19.6 m
3. If an object is thrown straight upward at 29.4 m/sec, it will stay in the air for
a. 3 sec.
b. 6 sec.
c. 0.33 sec
d. 288 sec.
e. 29.4 sec.
4. A cannon shoots a projectile at 200 m/sec at an angle of 30 degrees above horizontal. The vertical
velocity is
a. 9.8 m/sec
b. 400 m/sec
c. 173 m/sec
d. 231 m/sec
e. 100 m/sec
5. A cannon shoots a projectile at 200 m/sec at an angle of 30 degrees above horizontal. The
horizontal velocity is
a. 9.8 m/sec
b. 400 m/sec
c. 173 m/sec
d. 231 m/sec
e. 100 m/sec
6. A cannon shoots a projectile at 200 m/sec at an angle of 30 degrees above horizontal. The
projectile stays in the air for
a. 10.2 sec
b. 20.4 sec.
c. 40.8 sec
d. 17.7 sec
e. 35.5 sec
7. A cannon shoots a projectile at 200 m/sec at an angle of 30 degrees above horizontal. The
horizontal range of the cannon is
a. 1764 m
b. 3530 m
c. 7058 m
d. 2040 m
e. 4080 m
8. A marble moving at 2 m/sec rolls off a tabletop that is 1 m high. It hits the ground how many m
from the edge of the table top?
a. 0.500 m
b. 0.451 m
c. 0.225 m
d. 0.903 m
e. 2 m
9. A car’s velocity is 20 m/sec. Its brakes slow it down at -4 m/sec2 What distance is required to stop
the car?
a. 50 m
b. 5 m
c. 1.58 m
d. 0.25 m
e. 7.07 m
First Semester Exam Study Guide - Page 2
Unit 2 – Motion graphs
Slope = Rise/run = vertical unit / horizontal unit
Area = vertical unit x horizontal unit
Use the following graph to answer questions 16 - 18.
Velocity vs. Time
9
8
Y
Velocity (m/s)
7
6
5
X
4
Z
3
2
1
0
0
1
2
3
4
10. The velocity during Y is
a. 2 m/sec
b. 4 m/sec
5
6
7
Time (s)
c. 6 m/sec
8
d. 8 m/sec
11. The distance covered during the entire trip (X, Y and Z) is
a.64 m
b. 80 m
c. 10 m
d. 24 m
12. The acceleration during X is
a. 2 m/sec2
b. 4 m/sec2
c. 8 m/sec2
9
10
11
e. 32 m/sec
e. 8 m
d. 16 m/sec2 e. 9.8 m/sec2
12a. What does the slope of this graph represent?
12b. When the slope is 0, what does that mean?
Use the following graph to answer questions 19 - 23.
D
i
s
t
a
n
c
e
C
D
B
E
A
Time, s
m
13. Slope measures
a. distance
b. acceleration
c. velocity
d. time
e. nothing
14. Where is velocity greatest?
a. A
b. B
c. C
d. D
e. E
15. Where is velocity 0?
a. A
b. B
c. C
d. D
e. E
16. Where is velocity negative?
a. A
b. B
c. C
d. D
e. E
12
13
First Semester Exam Study Guide - Page 3
Unit 3 - Newton’s laws of motion
F=ma and Fnet=manet
True weight is always mg
FN = normal force, is always perpendicular to the surface of contact
Apparent weight is always equal to the Normal Force and may be greater than or less than true
weight
Free Body Diagrams
 Define the system
 Draw the force vectors
 Define the positive axis direction
 Fnet = manet
17. A man’s mass is 60 kg. His weight is
a. 588 N
b. 6.1 N
c. 0.16 N
d. 60 N
e. 9.8 N
18. When a 60 kg man is in an elevator accelerating upward at 4 m/sec2 his apparent weight is
a. 588 N
b. 60 N
c. 39.2 N
d. 348 N
e. 828 N
19. When a 60 kg man is in an elevator moving downward at a constant 4 m/sec his apparent
weight is
a. 588 N
b. 60 N
c. 39.2 N
d. 348 N
e. 828 N
20. The Atwood machine below has an acceleration of
a. 0.24 m/sec2 b. 3 m/sec2
c. 4.2 m/sec2
d. 9.8 m/sec2
21. The tension in the cord of the Atwood machine below is
a. 19.6 N
b. 29.4 N
c. 28 N
d. 68.6 N
e. 22.9 m/sec2
e. 11.2 N
5
kg
2
kg
22. What is the acceleration of this Atwood machine (no friction)?
a. 1.96 m/sec2
b. 5.88 m/sec2
c. 9.8 m/sec2
23. What is the tension in the cord?
a. 4.9 N
b. 9.8 N
c. 15.7 N
d. 19.6 N
d. 7.35 m/sec2
e. 14.4 m/sec2
e. 78.4 N
8 kg
2 kg
First Semester Exam Study Guide - Page 4
Unit 4 – Gravitation
Kepler’s Third Law
The square of the ratio of the periods of any two planets revolving about the Sun equal
to the cube of the ratio of their average distances from the Sun
rA3
____________
=
rB3
_____________
2
2
tA
tB
Newton’s Law of Universal Gravitation
Objects attract other objects with a force that is proportional to the product of their masses
and inversely proportional to the square of the distance between them
m1 m2
F = G
______________
G = 6.67 x 10
-11
2
N m / kg
2
r2
In order to determine the acceleration due to gravity for any planet (or satellite):
g =
G
me
___________
r2
24. An asteroid with a mass of 50,000 kg is 7000 m from the international space station which
has a mass of 275,000 kg. What is the force of gravitational attraction between the asteroid
and the space station?
25. What is the force of gravity on Mars?
26. How long does it take Mercury to orbit the sun?
First Semester Exam Study Guide - Page 5
Unit 5 – Force Vectors
Up forces = down forces
Left forces = right forces
Strings can only pull
Beams can push or pull
Weight is always a down force
Must have at least one of each force (up, down, left, and right)
27. What is the force in cable x?
a. 200 N
b. 400 N
d. 700 N
e. 800 N
c. 600 N
28. The cord’s force is
a. down and left
c. up and left
b. down and right
d. up and right
29. The bar’s force is
a. left
c. up
b. down
d. right
30. Draw the horizontal and vertical component
Vectors for cable A.
31. Draw the horizontal and vertical component
Vectors for cable B
32. What is the tension in each cable A?
33. What is the tension in cable B?
34. What is the force of cable A?
a. 271 N
b. 371 N
d. 671 N
e. 771 N
c. 471 N
35. In the crane diagram, the direction of A’s force is
a. down and left
b. down and right
c. up and left
d. up and right
36. In the crane diagram, the direction of B’s force
a. down and left
b. down and right
c. up and left
d. up and right
A
B
First Semester Exam Study Guide - Page 6
Unit 6 - Torque
Torque = a measure of how effectively a force causes rotation or equilibrium
T = force x distance
Torque clockwise = torque counterclockwise
Up = down
37. What is the weight of X?
a. 10 N
b. 20 N
c. 30 N
d. 40 N
e. 50 N
38. At what distance from the left end should a string be
attached so the apparatus will balance?
a. 2 m
b. 3 m
c. 4 m
d. 5 m
e. 6 m
39. The car weighs 10000 N. The bridge weighs 2000 N. The left bridge
support exerts an upward force of
a. 5000 N
b. 7000 N
c. 8000 N
d. 9000 N
e. 10000 N
First Semester Exam Study Guide - Page 7
Unit 7 - Friction
Ff = μ FN
SLIDE down the hill = SINE down the hill
Weight (Fw) always goes STRAIGHT down
Constant speed:
µ = tan Ө
No Friction:
acceleration = 9.8 sin Ө
40. If µ = 0.4, what force is necessary to push a 500 N
box across the floor?
a. 0.0008 N
b. 125 N
c. 200 N
d. 1250 N
e. 2000 N
41. If µ= 0.4 and you push a 100 kg box with a force of 500 N,
what is the acceleration?
a. 0.3 m/s2
b. 0.4 m/s2
c. 0.8 m/s2
d. 1.0 m/s2
e. 1.1 m/s2
42. A box slides down a 30° slope at constant speed.
What is µ?
a. 0.5
b. 0.87
c. 0.58
d. 9.8
e. 30
43. The coefficient of friction (µ) is 0.1. What is the acceleration of this Atwood machine?
a. 0.85 m/s2
b. 1.05 m/s2
c. 1.15 m/s2
d. 1.30 m/s2
e. 1.5 m/s2
First Semester Exam Study Guide - Page 8
Unit 8 - Circular Motion
Circular Motion Formula Page
ac
Fc
v2
= -----------r
m v2
= -----------r
vc =
√
T =2∏
rg
√
l/g
Pendulum
rollercoaster
yoyo
satelite
T =2∏
1 g = 9.8 m/s2
√m/k
Spring
44. A 2 kg object is twirled in a horizontal circle on a 1.6 m string at 4 m/s. What centripetal force
does the string exert?
a. 5 N
b. 10 N
c. 15 N
d. 20 N
e. 25 N
45. What is the period of pendulum with a length of 0.50 m?
a. 0.5 s
b. 0.8 s
c. 1.2 s
d. 1.4 s
e. 1.6 s
46. An amusement park ride makes you go around a circle of radius 4 m at 8 m/s. How many g’s of
centripetal acceleration do you feel?
a. 9.8 g’s
b. 1.6 g’s
c. 16 g’s
d. 2.4 g’s
e. 5 g’s
47. 5000 rev/min is how many radians/s?
a. 523
b. 47700
c. 1884000
d. 13.3
e. 6.28
First Semester Exam Study Guide - Page 9
NUMBER
ANSWER
NUMBER
ANSWER
NUMBER
1
C -39.2 m/s
16
D
31
2
A -78.4m
17
A 588 N
32
70.9 N
3
B 6s
18
E 828 N
33
169.6 N
4
E 100 m/s
19
A 588 N
34
E 771 N
5
C 173 m/s
20
C 4.2 m/s2
35
6
B 20.4 s
21
C 28 N
36
7
B 3530 m
22
A 1.96
m/s2
37
B 20 N
8
D .903 m
23
C 15.7 N
38
B3m
1.9 x 10
N
39
A 5000 N
-8
ANSWER
A down
and left
D up and
right
9
A 50m
24
10
D 8 m/s
25
40
C 200 N
11
A 64 m
26
41
E 1.1 m/s2
12
B 4 m/s2
27
E 800 N
42
C .58
13
C velocity
28
C up and
left
43
C 1.15
m/s2
14
C
29
D
44
D 20 N
15
B
30
45
D 1.4 s
NUMBER
ANSWER
46
B 1.6 g’s
47
A 523
rad/s