Instructions
This is an open resources exam. You may consult your own textbook, class notes, slides, equation sheet, internet, and any other material we post for you, but do not copy text, work, solutions, etc. and write it as your own answer to a problem.
Multiple-Choice Section
Instructions: This section contains multiple-choice questions. In order to receive full credit, you must select the co
ect answer question and show how you got each answer.
Question 1: Yeeting a Textbook
On a beautiful snowy Connecticut afternoon, you are reading your physics textbook near the ocean. After becoming frustrated with how te
ible the book is, you throw the book off a cliff into the ocean. Which of the following are the co
ect directions for the textbook’s velocity and acceleration when the textbook is at the highest point in its trajectory?
a) Velocity: zero. Acceleration: zero
) Velocity: horizontal. Acceleration: vertical
c) Velocity: horizontal. Acceleration: zero
d) Velocity: vertical. Acceleration: vertical
e) Velocity: vertical. Acceleration: zero
f) More information is required to answer this question
g) None of the above
Question 2: Forces of Attraction
Two cubes are held 0.25 m apart. At this distance, the cubes experience a force of 4 N. If the distance between the cubes is doubled, what force will the left cube experience?
a) 16 N
) 8 N
c) 4 N
d) 2 N
e) 1 N
f) More information is required to answer this question
g) None of the above
Question 3: Ice on Wate
Which of the following explanations accurately describes why ice floats on water?
a) Due to Bernoulli’s principle
) Due to Pascal’s principle
c) Due to Archimede’s principle
d) Due to Poiseuille’s equation
e) More information is required to answer this question
f) None of the above
Question 4: Sliding Snowball
During an intense snowball fight, a snowball slides along a patch of frictionless ice. One of the participants is a physics student, and she measures the velocity of the snowball over time. Which of the following graphs represents what you would expect to measure for the snowball?
Question 5: Sliding a Box
A box that is sliding across the floor experiences a net force of 10.0 N. If the box has a mass of 1.50 kg, what is the resulting acceleration of the box?
a) 0.07 m/s2
) 0.15 m/s2
c) 6.67 m/s2
d) 15.0 m/s2
e) More information is required to answer this question
f) None of the above
Question 6: Falling Feathe
A feather is falling toward the ground at a constant rate. Which of the following statements are true about the feather?
a) There cannot be any forces acting on the feather.
) There is no net force acting on the feather.
c) There can only be one force acting on the feather.
d) There can be only two forces acting on the feather.
e) More information is required to answer this feather.
f) None of the above.
Question 7: Making a Turn
A daredevil is driving a car in a circle with a radius of 12 feet while doing a donut. If the speed of the car is 10 miles per hour, what is the centripetal acceleration of the car?
a) 0.83 m/s2
) 1.7 m/s2
c) 5.5 m/s2
d) 8.3 m/s2
e) 14 m/s2
f) 8,800 m/s2
g) 44,000 m/s2
h) More information is required to answer this question
i) None of the above
Question 8: Bugatti Chiron
How much work is done to accelerate a Bugatti Chiron (1,996 kg) from rest to a velocity of 26.2 m/s over level ground?
a) 0 J
) 2.61x104 J
c) 6.85x105 J
d) 1.37x106 J
e) 2.74x106 J
f) 6.71x106 J
g) More information is required to answer this question
h) None of the above
Free Response Section
Instructions: In this section, you will be graded on how well you answer the questions and show and/or explain your work. PLEASE EXPLAIN/SHOW ALL YOUR WORK. You will receive zero credit for the co
ect answer without showing/explaining your answer.
Question 9: Hero Stuck on a Pond
Our hero is standing in the middle of a very large, frictionless ice pond. Since there is no friction, they cannot walk, crawl, jump, or slide to the edge. Using the idea of conservation of momentum, describe at least one way they could reach the edge.
Question 10: The Cube
During the lab you measure the volume of a cube to be 1,506 cubic centimeters.
A. Convert this volume measurement to m3.
B. Convert this volume measurement to milliliters.
C. What is the side length of the cube you measured?
Question 11: Fermi Estimate
Please use the Fermi Estimate process we learned in class to make the following estimate: How pieces of paper are used by UConn students each semester? Make sure to show your work and cite any outside sources you use to make your estimate.
Question 12: Accelerating a Particle
A constantly accelerating particle increases its velocity from 10 m/s to 20 m/s in 1.0 s. What is the particle’s acceleration during this time?
Question 13: Pulling a Sleigh
A sleigh is being pulled by eight magical reindeer and is sliding across the snow-covered ground at constant velocity.
A. Identify the forces acting on the sleigh.
B. Draw a free body diagram for the sleigh.
C. For the forces you identified in part A, what is the agent of each of the forces?
D. Are there any Newton’s third pairs (i.e., action-reaction pairs) in the force you identified in part A? If so, what are they? If not, why not?
Question 14: Driving a Ca
We know that an object cannot exert a net force on itself. Keeping this in mind, can you use Forces and Newton’s laws to explain how a car is able to move over a rough, surface?
Question 15: Helium in a Balloon
The picture below shows the interior of a balloon. On the left-hand side shows the balloon with a representative sample of Helium atoms inside the balloon. Notice that the atoms are all moving in random directions. The a
ows for each atom represent the velocity of that specific atom. On the right shows a zoomed-in segment of the balloon and a Helium atom. Each Helium atom has a mass of 6.64x10-27 kg. The Helium atom shown in the zoomed in picture is initially traveling perpendicularly toward the balloon and bounces off in exactly the opposite direction with the same magnitude of velocity. The initial velocity of the Helium atom has a magnitude of 1,360 m/s.
A. What is the initial momentum of this Helium atom? Include both magnitude and direction.
B. What is the final momentum of this Helium atom? Include both magnitude and direction.
C. What is the average force exerted by the Helium atom on the balloon wall if the collision occurs over 5.92x10-8 s? Include both magnitude and direction.
D. If the Helium atom has a cross-sectional radius of 31.0x10-12 m, what is pressure exerted on the balloon wall by this Helium atom?
Question 16: Throwing a Baseball
A baseball player throws a ball off a cliff as shown in the figure below. The ball falls until it hits the ground and the ball’s trajectory is the dotted line in the figure. Describe what types of energy the baseball has at the following locations:
A. Immediately after the baseball is thrown.
B. Halfway between where it is thrown and the ground.
C. Immediately before the baseball hits the ground.
Question 17: Pressure Cooker
An instant pot is a type of pressure cooker, which is a kitchen tool used to cook food quickly in a constant volume. If the air in a pressure cooker is initially at room temperature under atmospheric pressure, what will the internal temperature be when the internal pressure is increased to 206 kPa? Give your answer in K and °C.
You’ve reached the end of the exam. Congratulations!
PHYS XXXXXXXXXXSpring 2021 Equations
Table 1: Useful equations.
ρ =
m
V
density is mass over volume
v =
d
t
average speed is distance over time
a =
vf − vi
t
acceleration is change in velocity over time
d =
1
2
at2 distance is half acceleration times time squared
F = ma force is mass times acceleration
w = mg weight is mass times acceleration due to gravity
p = mv momentum is mass times velocity
ac =
v2
centripetal acceleration is velocity squared over radius
Fc = mac centripetal force is mass times centripetal acceleration
F = G
m1m2
d2
gravitational force is G times the product of two masses over distance squared
W = Fd work is force times distance
P =
W
t
power is work over time
KE =
1
2
mv2 kinetic energy is half mass times velocity squared
PE = mgh potential energy is mass times acceleration due to gravity times change in height
PV = nRT ideal gas law
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Table 2: Temperature conversions.
from Celsius to Kelvin TK = tC XXXXXXXXXX
to Fahrenheit tF = (1.8tC) + 32
from Fahrenheit to Kelvin TK =
tF−32
XXXXXXXXXX
to Celsius tC =
tF−32
1.8
from Kelvin to Celsius tC = TK − 273.15
to Fahrenheit 1.8(TK − XXXXXXXXXX
distance from The Sun to the Andromeda galaxy ≈ 2 million light years
speed of sound in air = XXXXXXXXXX · T m/s (T in ◦C)
speed of light in a vacuum (c) = 3 × 108 m/s
density of aluminum = 2.7 g/cm3
density of iron = 7.9 g/cm3
latent heat of fusion for water = 334 J/g
latent heat of vaporization for water = 2230 J/g
specific heat of liquid water = 4.184 J/g ◦C
specific heat of water ice = 1.865 J/g ◦C
specific heat of copper = 0.38 kJ/kg ◦C
fundamental charge of the electron = 1.60 × 10−19 C
G = 6.67 × 10−11 N m2/kg2 (Gravitational constant)
k = 9.00 × 109 N m2/C2 (Coulomb’s constant)
kB = 1.38 × 10−23 J/K (Boltzmann’s constant
R = 8.31 J/Kmol (Gas constant)
NA = 6.02 × 1023 particles/mol (Avogadro’s number)
g = 9.8 m/s2 (acceleration due to gravity near Earth’s surface)
h = 6.63 × 10−34 Js (Planck’s constant)
1 km = 1000 m
1 m = 100 cm
1 m = XXXXXXXXXXnm (10−9)
1 light year = 9.461 × 1012 km
1 inch = 2.54 cm
1 foot = 12 inches
1 hour = 60 minutes
1 minute = 60 seconds
1 kg = 1000 g
1 kg = 2.2 pounds
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