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Core Review Part 1
Standard 1: Students will understand how to measure, calculate, and describe the motion of an object in terms
of position, time, velocity, and acceleration.
Objective 1: Describe the motion of an object in terms of position, time, and velocity.
S1O1a: Calculate the average velocity of a moving object using data obtained from measurements of position
of the object at two or more times.
1) A cyclist is riding on a flat level road. A physics student tracks the position of the bike over time by finding the
position of the bike at specific clock readings. The data is collected and recorded in a table as shown in Table
1 below.
Time (s)
Position (m)
15
95
45
210
75
365
105
520
135
700
a) Calculate the displacement of the bike from 45 s to 105 seconds.
b) Calculate the displacement of the bike from 15 s to 75 seconds.
c) Calculate the average velocity of the bike from 15 s to 135 s.
d) Calculate the average velocity of the bike from 75 s to 105 s.
e) Calculate the average velocity of the bike from 45 s to 135 s.
2) The motion of a marble rolling on a carpeted surface is illustrated in the motion diagram below. The motion
of the marble is to the left and the position number of the marble at each time is displayed below the image
of the marble. The time interval between each image taken is 0.35 seconds.
Motion of the Marble
0.36 m
0.90 m
1.7 m
2.7 m
a) Calculate the displacement of the marble from position numbers 2.7 meters to 0.90 meters.
b) Calculate the average velocity of the marble from position numbers 1.7 meters to 0.90 meters.
c) Calculate the average velocity of the marble from position numbers 4.0 meters to 1.7 meters.
4.0 m
S1O1b: Distinguish between distance and displacement.
S1O1c: Distinguish between speed and velocity.
3) An ant travels as follows. The whole time it takes is 6 minutes. Report answers in cm/s or cm. Ant bed 
food source 1  ant bed food source 2; let to the left be the negative direction. Not to scale.
20 cm
Food source 2
40 cm
Ant bed
Food source 1
a) Calculate the ant’s displacement in cm.
b) Calculate the distance the ant traveled in cm.
c) Calculate the ant’s average speed in cm/s.
d) Calculate the ant’s average velocity in cm/s.
4) A ball is dropped 5 meters from the ground. The ball bounces off the ground up to a height of 3.25 meters. It
takes the ball 1.8 seconds to fall from 5 meters and bounce back up to 3.25 meters.
a) Calculate the displacement of the ball from its starting height to its ending height.
b) Calculate the distance the ball traveled from its starting height to its ending height.
c) Calculate the average speed of the ball from its starting height to its ending height.
d) Calculate the average velocity of the ball from its starting height to its ending height.
S1O1d: Determine and compare the average and instantaneous velocity of an object from data showing its
position at given times.
5) The following data tables represents the position at specific clock readings of students walking down a
hall.
Student A
Student B
Position (m)
Time (s)
Position (m)
Time (s)
0
0
0
2
2
1
4
4
6
2
12
6
12
3
13
8
a) Calculate the average velocity of Student A
from 0 seconds to 3 seconds.
c) Calculate the average velocity of Student B
from 4 seconds to 8 seconds.
b) During which time interval was Student A
traveling the fastest?
i.
From 0 s to 1 s
iii. From 2 s to 3 s
ii.
From 1 s to 2 s
d) During which time interval was Student B
traveling the fastest?
i.
From 2 s to 4 s
ii. From 6 s to 8 s
ii.
From 4 s to 6 s
S1O1e: Collect, graph, and interpret data for position vs. time to describe the motion of an object and compare
this motion to the motion of another object.
6) Below is a position vs. time graph. Answer all questions associated with the graph.
Postions-Time Graph
15
Postions (m)
10
5
0
-5
-10
0
2
4
6
8
10
12
14
Time (s)
a) Write a time interval in which the object is
standing still:
d) Calculate the average velocity of the object
from 2 seconds to 5 seconds.
b) Write a time interval in which the object is
moving in the negative direction:
e) Calculate the instantaneous velocity of the
object at 11 seconds.
c) Write a time interval in which the object is
moving in the positive direction:
7) Match the following scenarios to the position vs. time graphs. Write the letter next to the graph.
a) Starting from rest away from the origin, a truck accelerates and then travels at a constant speed,
getting farther and farther from the origin.
b) A dog is running fast back toward the origin, but slows as he goes.
c) An ant crawls slowly at constant speed away from a starting position.
d) A ball is thrown upward and turns around and comes back down. Consider the origin to be at the
beginning of the throw.
e) Shandra passes the origin at her top speed, continues at this speed away from the origin for a couple
of seconds and then slows to a stop.
f) A nervous sophomore driver slowly backs (at constant speed) toward the origin.
I
II
x
III
x
x
t
t
t
V
IV
x
VI
x
t
x
t
t
Objective 2: Analyze the motion of an object in terms of velocity, time, and acceleration.
S1O2a: Determine the average acceleration of an object from data showing velocity at given times.
8) The following data tables represents the velocity at specific clock readings of students running down a
hall.
Student A
Student B
Velocity (m/s)
Time (s)
Velcoity (m/s)
Time (s)
0
0
0
2
1
1
2
4
3
2
5
6
6
3
9
8
a) Calculate the average acceleration of Student
A from 0 seconds to 3 seconds.
c) Calculate the average acceleration of Student
B from 2 seconds to 6 seconds.
b) During which time interval did Student A have
the lowest acceleration?
i.
From 0 s to 1 s
iii. From 2 s to 3 s
ii.
From 1 s to 2 s
d) During which time interval did Student B have
the lowest acceleration?
i.
From 2 s to 4 s
iii. From 6 s to 8 s
ii.
From 4 s to 6 s
S1O2b: Describe the velocity of an object when its acceleration is zero.
S1O2c: Collect, graph, and interpret data for velocity vs. time to describe the motion of an object.
9) Below is a velocity vs. time graph. Answer all questions associated with the graph.
Velocity (m/s)
Velocity-Time Graph
2.5
2
1.5
1
0.5
0
-0.5 0
-1
-1.5
-2
-2.5
Time (s)
1
2
3
4
5
6
7
8
9
10
11
12
13
a) Write a time interval or intervals in which the
object is moving in the negative direction:
g) Find the velocity of the object at 4 seconds.
b) Write a time interval or intervals in which the
object is moving in the positive direction:
h) Find the acceleration of the object at 4 s.
c) Write a time interval or intervals in which the
object is speeding up:
i)
Find the average acceleration of the object from
2 seconds to 8 seconds.
d) Write a time interval or intervals in which the
object is slowing down:
j)
Find the average acceleration of the object from
6 seconds to 12 seconds.
e) Find the velocity of the object at 3 seconds.
k) Describe the motion of the object from 0 seconds
to 3 seconds.
f)
l)
Find the acceleration of the object at 2 s.
Describe the motion of the object from 7 seconds
to 11 seconds.
10) Matching- match the scenarios with the following velocity vs. time graphs.
a) Starting from rest, a student drives a car in the positive direction and then reaches a constant velocity
for a couple of seconds and then slows for a stop sign and comes to a stop.
b) Starting from rest, a student throws a car into reverse and goes back toward the origin speeding up as
she goes.
c) Let the ground be the origin. A helicopter hovers above the ground without moving and then begins
to accelerate upward.
d) A ball is thrown straight upward and slows down with uniform acceleration, then reaches its highest
point and falls down speeding up as it goes. The ball is going pretty fast when it leaves the thrower’s
hand.
e) A student rolls a ball up an incline. Let the bottom of the incline be the origin. The ball is going pretty
fast at the bottom. The ball slows as it rolls upward away from the origin.
f) A student walks home at a constant velocity of 2 m/s. Let the origin be the school.
+
v
I
0
+
v
t
-
+
v
0
-
II
0
+
v
t
-
IV
+
v
t
0
-
III
0
t
-
V
+
v
t
VI
0
t
-
S1O2d: Describe the acceleration of an object moving in a circular path at constant speed.
11) A race car moves around a circular track at a constant speed. We are looking down at it from above.
Draw velocity and acceleration vectors for the car when it is at the position shown.
= race car
Objective 3: Relate the Motion of objects to a frame of reference.
12) Here are Student A, Student B and Student C walking along a sidewalk: A =
; B=
; C=
East
West
6 m/s
4 m/s
8 m/s
All velocities shown are relative to the ground.
Complete the following table by filling in the motion of each person relative to the given individual:
Student A
Student B
Student C
Relative to Student A
Relative to Student B
Relative to Student C
Objective 4: Use Newton’s first law to explain the motion of an object.
13) A student exerts a constant horizontal force on a box. The box then moves across a horizontal floor at a
constant speed. The constant horizontal force applied by the student:
a) Has the same magnitude as the weight of the box.
b) Is greater than the weight of the box.
c) Is greater than the friction force which resists the motion of the box.
d) Is greater than either the weight of the box or the friction force which resists its motion.
e) Has the same magnitude as the friction force which resist the motion of the box.
14) If the student in the previous problem suddenly stops applying a horizontal force to the box, then the box
will:
a) Immediately come to a stop.
b) Continue moving at a constant speed for a while and then slow to a stop.
c) Immediately start slowing to a stop.
d) Continue at a constant speed.
e) Increase its speed for a while and then start slowing to a stop.
15) A shopper at a grocery store is pushing a shopping cart and the cart is speeding up. There exists an
applied force from the shopper and a friction force acting on the cart. How do the magnitudes of these
two forces compare?
a) The applied force is greater than the friction force
b) The applied force is less than the friction force
c) The applied force is equal to the friction force
d) Nothing can be said about these forces without more information.
16) A student is in an elevator standing on a bathroom scale. When the elevator is at rest the scale reads 750
N. Later on the elevator is moving upward at a constant speed. Which one of the following scale readings
could be read from the scale as the student is moving upward at the constant speed in the elevator?
a) 0 N
b) 650 N
c) 750 N
d) 850 N
17) The same student is in the elevator in the previous problem but now the elevator is moving upward and
slowing down. Determine how the magnitude of the normal force compares to the magnitude of the
gravitational force acting on the person. Choose the one answer that has the best explanation.
a) The magnitude of the normal force is greater than the magnitude of the gravitational force.
b) The magnitude of the normal force is less than the magnitude of the gravitational force.
c) The magnitude of the normal force is equal to the magnitude of the gravitational force.
d) There exists no normal force acting on the student.
e) Nothing can be said about these forces without more information.
Standard 2: Students will understand the relation between force, mass, and acceleration.
Objective 1: Analyze forces acting on an object.
Write 1st, 2nd or 3rd law in each blank for the law the best explains the situation.
_________ 18) An object’s acceleration is proportional to the net force on it and inversely proportional to its
mass.
_________19) An object in motion stays in motion unless acted upon by an unbalanced force; an object at rest
stays at rest unless acted upon by an unbalanced force.
_________ 20) There are two objects that move together. One stops and the other doesn’t. At first we are
surprised that both do not stop; but then we realize that the stopping force really only acted on one of the objects
(and the other one remained in motion).
_________ 21) Someone not wearing a seat belt is thrown forward into the windshield when a car stops abruptly.
_________22) A package in the back of a pick-up truck slides forward when the driver brakes.
_________23) You are skateboarding and your skateboard hits a curb and you fly forward.
_________ 24) To apply this law, you consider the forces acting on two different objects.
________ 25) A person throws a baseball (mass of about 0.5 kg) and then a shot put (mass of about 7 kg) with
the same force each time. She notices that the shot put has LESS acceleration than the baseball for identical
throws.
_________ 26) A person throws a baseball (mass of about 0.5 kg) once and then again with twice the force. The
throw that had twice the force had twice the acceleration.
Objective 2: Using Newton’s Second law, relate the force, mass and acceleration of an object.
27) For the same object (same mass) as net force increases the acceleration ______________.
Circle the graph that most accurately shows this relationship
a
a
a
F
F
F
28) For the same net force, as the mass of the object increases, the acceleration __________________.
a
a
m
a
m
m
29) What is the gravitational force on a person of mass 70 kg?
30) What is the gravitational force on a cat of mass 3.2 kg?
31) What is the mass of an object of weight 100 N?
32) What is the mass of an object of weight 68 N?
33) If you use a horizontal force of 720 N to slide a 95 kg wooden crate across a floor at a 4.5 m/s2 acceleration in
the same direction as the horizontal force,
a) Draw a free-body diagram of the situation.
b) Find the magnitude of the friction force acting on the crate.
The following velocity-time graph is of car traveling along a flat level road. There exists an applied force to the
right (+) and a friction force to the left (-). The freebody (vector) diagram below represent the situation.
Sometimes the applied force is greater than the friction force and sometime it is does not. Note: Velocity is in
m/s on the graph.
Velocity (m/s)
Ff
FApp
35
30
25
20
15
10
5
0
-5
-10
-15
-20
0
5
10
15
20
25
30
35
40
Time (s)
34) From time 0 seconds to 5 seconds
a) Is the velocity of the car to the left, to the
right or zero?
35) From time 25 seconds to 40 seconds
a) Is the velocity of the car to the left, to the
right or zero?
b) Is the acceleration of the car: negative,
positive or zero?
b) Is the acceleration of the car: negative,
positive or zero?
c) Is the net force acting on the car negative,
positive or zero?
c) Is the net force acting on the car negative,
positive or zero?
d) Which force is greater Ff or FApp or are
they equal.
d) Which force is greater Ff or FApp or are
they equal.
e) Which of Newton’s Laws is best applied
during this time interval: 1st Law or 2nd
Law?
e) Which of Newton’s Laws is best applied
during this time interval: 1st Law or 2nd
Law?
f)
f)
Find the value of the car’s acceleration in
m/s2.
g) Find the value of the Net force applied to
the 850 kg car in N.
Find the value of the car’s acceleration in
m/s2.
g) Find the value of the Net force applied to
the 850 kg car in N.
Objective 3: Explain that forces act in pairs as described by Newton’s third law.
36) Find the magnitude and direction of each force. These are called action-reaction pairs.
a) A semi hits a Smart car with a force of 100,000 N (toward the Smart Car). With what force (magnitude
and direction) does the Smart car hit the semi?
b) Jonathan bats a ball with a force of 200 N toward the ball. With what force (magnitude and direction)
does the ball hit the bat?
c)
Alisha, the biggest girl bully in school, smacks Amy across the face with a force of 68 N toward Amy’s
face. With what force (magnitude and direction) does Amy’s face hit Alisha’s hand?
d)
An asteroid pulls on earth with a force of 40,000 N – toward the asteroid. With what force (magnitude
and direction) does earth pull on the asteroid?
e)
A charged balloon pulls on a small piece of paper with a force of 0.4 N- toward the balloon. With what
force (magnitude and direction) does the paper pull on the balloon?
f)
A person is walking. As he takes a step, his foot pushes backward on the floor with a force of 50 N. With
what force (magnitude and direction) does the floor push on his foot?