Semester 1 Physics 101 Review Questions

Semester 1 Physics Review Questions
1)  Consider the earth, orbiting the sun for a year. Make a comparison between the displacement and the distance the
earth travels.
2)  You drive 6.00 km at 50.0 km/h and then another 6.00 km at 90.0 km/h. Your average speed over the 12.0 km
drive will be _________.
3)  The slope of a line connecting two points on a position versus time graph represents the objects _______.
4)  The slope of a tangent line at a given time on a position versus time graph represent the objects  _________
5)  The slope of a tangent line at a given time value on a velocity versus time graph gives  ________.
6) Define average velocity
7)  Define acceleration
8)  Suppose that a car traveling to the East (+x direction) begins to slow down as it approaches a traffic light.  Make
a statement concerning the direction of its acceleration.
9)  The area under the curve of a velocity versus time graph gives represents the object's_________
10)  A stone is thrown straight up. When it reaches its highest point, describe the velocity and acceleration of the
stone.
11)  Suppose a ball is thrown straight up, reaches a maximum height, then falls to its initial height.  Make a
statement about the direction of the velocity and acceleration as the ball is going up.
Figure 2-6      
12)  Refer to Figure 2-6. If you start from the Bakery, travel to the Cafe, and then to the Art Gallery, what is the
distance you have traveled?
Figure 2-7
13)  Figure 2-7 represents the position of a particle as it travels along the x-axis. What is the magnitude of the average
velocity of the particle between t = 1 s and t = 4 s
14) In Figure 2-7 (above), at what value of t is the speed of the particle equal to zero?
Figure 2-10
15)  Figure 2-10 shows the velocity-versus-time graph for a basketball player traveling up and down the court in a
straight-line path. Find the net displacement of the player for the 8 s shown on the graph.
16)  For figure 2-10, find the acceleration      a)  from t = 0 sec to t = 2 sec        b)  from t = 4 sec to t = 8 sec17)  An airplane starts from rest and accelerates at 10.8 m/s
2
. What is its speed at the end of a 400. m-long runway?
18)  A car is traveling with a constant speed when the driver suddenly applies the brakes, giving the car a deceleration
of 3.50 m/s
2
. If the car comes to a stop in a distance of 30.0 m, what was the car's original speed?
19)  An object is thrown upwards with a speed of 14.0 m/s. How long does it take it to reach its maximum height?
20)  An object is thrown up with a speed of 14 m/s. How high above the projection point is it after 0.50 s?
21)  To determine the height of a bridge above the water, a person drops a stone and measures the time it takes for it
to hit the water. If the time is 2.3 s, what is the height of the bridge?
22)  A model rocket rises with constant acceleration to a height of 3.2 m, at which point its speed is 26.0 m/s . How
much time does it take for the rocket to reach this height?
23)  A model rocket rises with constant acceleration to a height of 3.2 m, at which point its speed is 26.0 m/s . What
was the magnitude of the rocket's acceleration?
24)  Which quantities that we have used this year in Physics are scalar quantities?
25)  Which quantities that we have used this year in Physics are vector quantities?
26)  A soccer player carries the ball for a distance of 40.0 m in the direction 42.0° west of south. Find the westward
component of the ball's displacement.
27)  For general projectile motion, which statement is true when the projectile is at the highest point of its trajectory?
A) The horizontal and vertical components of its velocity are zero.
B) Its velocity and acceleration are both zero.
C) Its velocity is perpendicular to the acceleration.
D) The horizontal component of its velocity is zero.
E) Its acceleration is zero
28)  A pilot drops a bomb from a plane flying horizontally at a constant speed.  Neglecting air resistance, where will
the horizontal location of the plane be when the bomb hits the ground? (relative to the bomb)
29)  A rock is thrown at 60° above the horizontal with a velocity of 40 m/s. It reaches its highest point and starts
falling down. What is the velocity of the rock at the highest point of its trajectory?
30)  A student kicks a soccer ball in a high arc toward the opponent's goal. Neglecting air resistance, describe the
velocity and acceleration on its way up in its trajectory.
31)  A bullet is fired from ground level with a speed of 150 m/s at an angle 30.0° above the horizontal at a location
where g = 10.0 m/s
2
. What is the vertical component of its velocity when it is at the highest point of its
trajectory?
32)  The horizontal and vertical components of the initial velocity of a football are 16 m/s and 20 m/s respectively.
How long does it take for the football to rise to the highest point of its trajectory?
33)  A ball is thrown horizontally with an initial velocity of 40 m/s from a height of 10 m. How long will it take for
the ball to touch the ground, neglecting air resistance?
34)  A ball rolls over the edge of a building with a horizontal velocity 3.20 m/s. The horizontal range of the ball from
the base of the table is 20.0 m. How tall is the building, neglecting air resistance?
35)  A ball is thrown with an initial speed of 60 m/s at an angle of 30° above the horizontal. What is the ball's
horizontal displacement at the end of 4 seconds?
36)  A boy kicks a football from ground level with an initial velocity of 20 m/s at an angle of 60° above the
horizontal. What is the horizontal distance to the point where the football hits the ground?37)  A boy kicks a football with an initial velocity of 28.0 m/s at an angle of 30.0° above the horizontal. What is the
highest elevation reached by the football in its trajectory?
38)  A crow is flying horizontally with a constant speed of 2.70 m/s when it releases a clam from its beak. The clam
lands on the rocky beach 2.10 s later. Just before the clam lands, what is (a) its horizontal component of velocity,
and (b) its vertical component of velocity? (c) its resultant velocity and the angle it makes below the horizontal?
39)  In the absence of an external unbalanced force, a moving object will do what as time goes on?
40)  An object is moving with constant velocity.   a) What can you say about the net force?
b) If there are forces acting on the object, what can you conclude about the forces?
41)  When a parachutist jumps from an airplane, he eventually reaches a constant speed, called the terminal velocity.
This means what regarding forces?  Draw a FBD
42)  A 8000kg truck is towing a 2000kg car. The force exerted by the truck on the car is 6000 N. The force exerted by
the car on the truck is ________.
43)  A 0.30 kg ball is thrown up into the air. Ignore air resistance. When it is reaches its maximum height, the net
force acting on it is _______.
44)  The elevator in the Space Needle is going down. When the tension pulling up on the elevator is equal to the
elevator's weight, what happens to the motion of the elevator?
45)  You ride on an elevator that is moving downward with constant speed while standing on a bathroom scale. How
does the reading on the scale compare to your true weight, mg
46)  A block of mass 55kg slides down a frictionless plane inclined at an angle 17° with the horizontal.  The normal
force exerted by the plane on the block is?
47)  An object rests on an inclined surface. If the inclination of the surface is made steeper, what does the normal force
on the object do?
48)  Two objects have masses m and 5m, respectively. They both are placed side by side on a frictionless inclined
plane and allowed to slide down from rest. It takes the heavier object _____times longer/shorter to reach the
bottom of the incline than the lighter.
49)  In a particle accelerator, a proton reaches an acceleration of 9.0 x 10
13
m/s
2
. The mass of a proton is
1.7 x 10
-27
kg. What is the net force on the proton?
50)  A flatbed truck is carrying a load of timber which is not tied down. The mass of the timber is 899 kg. The
maximum static frictional force between the truck bed and the load is 5488 N. What is the highest acceleration
that the truck can have without losing its load? What is the static coefficient of friction between the load and truck
bed?
51)  A 1250 kg boat is pulling a 72 kg water skier on a calm lake. Friction is negligible. The boat accelerates with an
acceleration of 1.3 m/s
2
. What is the force exerted on the skier by the tow rope?
52)  A 50.0 kg crate is being pulled along a horizontal frictionless surface. The pulling force is 10.0 N and is directed
20.0° above the horizontal. What is the acceleration of the crate?
53)  A 40.0 kg box is being pushed along a horizontal frictionless surface. The pushing force is 15.0 N directed at an
angle of 15.0° below the horizontal. What is the normal force exerted on the crate by the ground?
54)  A person has a mass of 45 kg. How much does she weigh?  How much less does she weigh on the Moon, where
g = 1.62 m/s
2
?55)  A 40.0-kg crate is being lowered by means of a rope. Its downward acceleration is 2.00 m/s
2
. What is the force
exerted by the rope on the crate?
56)  A 36.0-kg child steps on a scale in an elevator. The scale reads 400. N. What is the direction and magnitude of
the acceleration of the elevator?
57)  A tightrope walker with a mass of 60.0 kg stands at the center of a rope which was initially strung horizontally
between two poles. His weight causes the rope to sag symmetrically, making an angle of 4.80° with the
horizontal. What is the tension in the rope?
58)  A 10.0 kg picture is held in place by two wires, one hanging at  50.0° to the left of the vertical and the other is
horizontal. What is the tension in the wires?
Figure 5-27
59)  A skier speeds down a trail, Figure 5-27.  The surface is frictionless and inclined at an angle of 22.0° with the
horizontal. Find the acceleration of the skier.
60)  A 2500 kg car accelerates from 0 to 21m/s in 5.2s. What is the friction force with the road, neglecting air
resistance?
Figure 6-1
61)  In Figure 6-1, the block of mass 43.6 kg is at rest on an inclined plane that makes an angle of 25.1° with the
horizontal. What is the force of static friction?
62)  Bobby (61kg) and Wayne (98kg) get in a tussle on the ice in a hockey game. If Bobby pushes Wayne with a force
of 77N what is the acceleration of each backwards?  Neglect friction.
63)  A tired mom puts a 0.200 kg latte on the roof of her car and forgets it. The coefficient of static friction between
the cup and the roof is 0.400. What is the maximum acceleration that the car can have if the cup is to stay in
place?
64)  A horse pulls a 555 kg sleigh across a level snow covered field at constant speed. The coefficient of friction,  µ,
is 0.15 between the sleigh and the snow.  What is the force exerted on the horse by the sleigh?
Figure 6-11  
65)  Two masses are connected by a string which goes over an ideal pulley as shown in Figure 6-11. Block A has a
mass of 3.0 kg and can slide along a frictionless plane inclined 30° to the horizontal. What is the mass of block
B if the system is in equilibrium?Figure 6-12    
66)  Refer to Figure 6-12. Block A has a mass of  3.00 kg and rests on a frictionless table and is connected to block
B, which has a mass of  2.00 kg, after passing over an ideal pulley, as shown. Block B is released from rest.
What is the acceleration of the system?
Figure 6-10
67)  A 3.00-kg mass (M1
) and a 5.00-kg mass (M2
) hang vertically at the ends of a rope that goes over an ideal pulley
(Figure 6-10). If the masses are released, what is the resulting acceleration of the system?
Answers:
1. The
displacement
is
zero,
the
distance
is
quite
large.
2. less
than
64.3
km/h
3. average
velocity
4. instantaneous
velocity
5. instantaneous
acceleration
6. vav

=
∆d/∆t
7. 
a
=
∆v/∆t
8. The
car
is
decelerating,
and
its
acceleration
is
negative
and
points
West
(‐x
direction)
9. Displacement
10. its
velocity
is
zero
and
its
acceleration
is
straight
down
.
11. Its
velocity
points
straight
upward
and
its
acceleration
points
straight
downward
12. 10.5
km
13. 0.67
m/s
14. 3
s
15. 18
m
16. a)

2
m/s
2






b)

0
m/s
2
17. 93.0
m/s
18. 14.5
m/s
19. 1.43
s
20. 5.8
m
21. 26
m
22. 
0.25
s
23. 110
m/s
2
24. mass,
time,
speed,
distance
25. displacement,
velocity,
acceleration,
force,
weight
26. 26.8
m
27. Its
velocity
is
perpendicular
to
the
acceleration
28. it
will
be
directly
over
the
bomb
29. 20
m/s
horizontal
30. Vertical
velocity
is
decreasing
at
9.81
m/s
2
,
Horizontal
velocity
remains
constant,
Acceleration
is
9.81m/s
2
down.
31. 0
m/s
32. 2.0
s
33. 1.4
seconds
34. 192m
35. 210
m
36. 35
m
37. 10.0
m
38. 
(a)
2.70
m/s



(b)
‐20.6
m/s



(c)
20.8m/s,
82.5°
39. move
with
constant
velocity
40. (a)
The
net
force
on
the
object
is
zero
(b)
they
are
balanced
41. the
force
of
air
resistance
is
equal
and
in
opposite
in
direction
to
the
weight
of
the
parachutist
42. 6000
N,
they
are
a
third
law
force
pair
43. equal
to
its
weight,

2.9
N
44. The
elevator
continues
to
descend
with
constant
speed
45. equal
to
your
true
weight,
mg
46. 520N
47. decreases
48. The
two
objects
reach
the
bottom
of
the
incline
at
the
same
time
49. 1.5
x
10
‐13

N
50. 6.10
m/s
2
,

0.622
51. 94
N
52. 0.188
m/s
2
53. 396
N
54. 440
N,

367
N
less
55. 312
N
56. 1.30
m/s
2
57. 3520
N
58. 153
N
in
angled
wire,

117
N
in
horizontal
wire
59. 3.67m/s
2
60. 10,000
N
61. 181
N
62. Bobby
1.3
m/s
2
,

Wayne
0.79
m/s
2
63. 3.92
m/s
2
64. 820N
65. 1.5
kg
66. 3.92
m/s
2
67. 2.45
m/s
2