PHYS Straighterline UPDATED Exam
Questions and CORRECT Answers
An amusement park game consists of throwing a quarter into a small bowl. If you win, you
get to take home a giant purple stuffed elephant. The dish is on a shelf that is 0.4 m above the
point where the quarter leaves your hand. The horizontal distance between the bowl and the
place where the quarter leaves your hand is 1.8 m. Ignoring air drag, if you toss the quarter at
an angle of 60°, what initial velocity is needed to bring home the giant purple stuffed
elephant? - CORRECT ANSWER- 4.8 m / s
If the x-component of a vector is 3 and the y-component is 4, what is the magnitude of the
vector? - CORRECT ANSWER- 5
Which of the following is involved in uniform circular motion? - CORRECT ANSWER-
constant angular velocity
As shown, a crate of oranges and a crate of apples, each with a different mass, are attached by
a rope (with tension Toa). A second rope (To ) is attached to the crate of oranges, and the
entire system is pulled with a constant acceleration a by this rope. Which of the following is
true of the tensions? - CORRECT ANSWER- Toa > To
How can you calculate the magnitude of a vector using scalar products? - CORRECT
ANSWER- Multiply it by itself and take the square root.
Suppose you weigh an object and the reading you get from the scale is 0.0070 kg. How many
significant digits does your measurement have? - CORRECT ANSWER- Two
Consider two objects sliding down an incline without rolling. If the objects don't have the
same mass, the heavier object will accelerate at a faster rate than the lighter one. - CORRECT
ANSWER- false
Which of the following statements concerning friction between the surfaces of two objects is
correct? - CORRECT ANSWER- The force of friction mostly depends on the nature of the
two surfaces.
,Calculate x=vt+1/2at2, where v = 0.227 m/s. t = 11.1s, and a = 9.80 m/s2. - CORRECT
ANSWER- 606 m
Which of the following statements concerning friction is incorrect? - CORRECT ANSWER-
The force of static friction ( fs ) between parallel surfaces in contact is given by: fs = μsN.
A car travels with a speed of 3.5 m / s, and then accelerates to 5.5 m / s in 4 s. Which of the
following is the average acceleration of the car? - CORRECT ANSWER- 0.5 m / s2
If the cross product of a vector of length 5 and a vector of length 3 results in a vector of
length 10, what is the angle between them? - CORRECT ANSWER- 42°
A vector is quantity that requires both magnitude and ________. - CORRECT ANSWER-
direction
King Kong is holding a woman on top of a skyscraper when she suddenly slips out of his
hand. How tall is the building if Superman has a minimum time of 2.30 s to catch the woman
before she hits the ground? - CORRECT ANSWER- 25.9 m
Kylie throws Kyra a kiwi. The kiwi leaves Kylie's hand at a height of 1.3 m from the ground
and Kyra grabs it out of the air at a height of 1.6 m. Kylie throws the kiwi at an angle of 33°
relative to the horizontal. The kiwi is in the air for 1.1 s. How far apart are Kylie and Kyra
standing? (Assume there is no drag force that no wind is blowing.) - CORRECT ANSWER-
9.6 m
A projectile is launched from a height of 250 m with initial horizontal velocity of 50 m/s.
What is the horizontal range of the projectile? - CORRECT ANSWER- 357 m
Imagine that you push down on an object that is sitting on a frictionless table. Which of the
following diagrams includes all the forces acting on the object? - CORRECT ANSWER- F W
down, N up
Your cat chases a spider across the floor. Its position is a function of time is r + (1.2m/s)ti +
(0.7m + (0.5m/s2)t2)j, where the origin is the southwest corner of the floor. Find the average
speed of the cat between t = 0.0s and t = 4.0s - CORRECT ANSWER- 2.3 m/s
, The position of an object along the x-axis is described by the formula x = 3t 2 − 2t. Which of
the following are the correct formulas for the velocity and acceleration of the object? -
CORRECT ANSWER- v = 6t − 2, a = 6
Using the conversion factor between kilograms and pounds, 1 kg = 2.205 lb, calculate how
many pounds are in 2.00 kg. - CORRECT ANSWER- 4.41 lb
An experimental new ride at an amusement park begins by spinning patrons about a circle of
radius R with constant speed v. At some point during the ride the speed doubles and the
spokes extend, doubling the radius. After this occurs, what is the acceleration of the patrons
in terms of the original acceleration, a ? - CORRECT ANSWER- 2a
Consider a mass of 85kg lying on the ground. The coefficient of static friction between them
is us = 0.65. What is the minimum force you need to apply in order to slide the mass? -
CORRECT ANSWER- 541 N
When turning around a circle, a car is subject to a continuous force, but its speed does not
necessarily change. Why is this true? - CORRECT ANSWER- The speed is not changing, but
the direction is.
A small mass is placed on a turntable that is rotating at 45 rpm. The centripetal acceleration is
____________. - CORRECT ANSWER- greater when the mass is farther from the center of
the circle
How many significant figures are in the quantity
9.86 m/s 2? - CORRECT ANSWER- 3
Laura is listening to a record spinning at 45 rpm (revolutions per minute). When she switches
the speed selector on the record player to 33 rpm, it takes 2.7 seconds for the record player to
change to the new speed. How many revolutions does the record make during this time?
Assume that the angular acceleration of the record is constant. - CORRECT ANSWER- 1.8
A 309 g glass rolls down an incline and onto a horizontal platform where it hits a beverage
can that is laying at rest on its side. The top of the incline is 11.0 cm above the horizontal
platform. The beverage can is initially at rest and weighs 7.35 N. Which of following is the
final velocity of the glass? - CORRECT ANSWER- −0.612 m / s
Questions and CORRECT Answers
An amusement park game consists of throwing a quarter into a small bowl. If you win, you
get to take home a giant purple stuffed elephant. The dish is on a shelf that is 0.4 m above the
point where the quarter leaves your hand. The horizontal distance between the bowl and the
place where the quarter leaves your hand is 1.8 m. Ignoring air drag, if you toss the quarter at
an angle of 60°, what initial velocity is needed to bring home the giant purple stuffed
elephant? - CORRECT ANSWER- 4.8 m / s
If the x-component of a vector is 3 and the y-component is 4, what is the magnitude of the
vector? - CORRECT ANSWER- 5
Which of the following is involved in uniform circular motion? - CORRECT ANSWER-
constant angular velocity
As shown, a crate of oranges and a crate of apples, each with a different mass, are attached by
a rope (with tension Toa). A second rope (To ) is attached to the crate of oranges, and the
entire system is pulled with a constant acceleration a by this rope. Which of the following is
true of the tensions? - CORRECT ANSWER- Toa > To
How can you calculate the magnitude of a vector using scalar products? - CORRECT
ANSWER- Multiply it by itself and take the square root.
Suppose you weigh an object and the reading you get from the scale is 0.0070 kg. How many
significant digits does your measurement have? - CORRECT ANSWER- Two
Consider two objects sliding down an incline without rolling. If the objects don't have the
same mass, the heavier object will accelerate at a faster rate than the lighter one. - CORRECT
ANSWER- false
Which of the following statements concerning friction between the surfaces of two objects is
correct? - CORRECT ANSWER- The force of friction mostly depends on the nature of the
two surfaces.
,Calculate x=vt+1/2at2, where v = 0.227 m/s. t = 11.1s, and a = 9.80 m/s2. - CORRECT
ANSWER- 606 m
Which of the following statements concerning friction is incorrect? - CORRECT ANSWER-
The force of static friction ( fs ) between parallel surfaces in contact is given by: fs = μsN.
A car travels with a speed of 3.5 m / s, and then accelerates to 5.5 m / s in 4 s. Which of the
following is the average acceleration of the car? - CORRECT ANSWER- 0.5 m / s2
If the cross product of a vector of length 5 and a vector of length 3 results in a vector of
length 10, what is the angle between them? - CORRECT ANSWER- 42°
A vector is quantity that requires both magnitude and ________. - CORRECT ANSWER-
direction
King Kong is holding a woman on top of a skyscraper when she suddenly slips out of his
hand. How tall is the building if Superman has a minimum time of 2.30 s to catch the woman
before she hits the ground? - CORRECT ANSWER- 25.9 m
Kylie throws Kyra a kiwi. The kiwi leaves Kylie's hand at a height of 1.3 m from the ground
and Kyra grabs it out of the air at a height of 1.6 m. Kylie throws the kiwi at an angle of 33°
relative to the horizontal. The kiwi is in the air for 1.1 s. How far apart are Kylie and Kyra
standing? (Assume there is no drag force that no wind is blowing.) - CORRECT ANSWER-
9.6 m
A projectile is launched from a height of 250 m with initial horizontal velocity of 50 m/s.
What is the horizontal range of the projectile? - CORRECT ANSWER- 357 m
Imagine that you push down on an object that is sitting on a frictionless table. Which of the
following diagrams includes all the forces acting on the object? - CORRECT ANSWER- F W
down, N up
Your cat chases a spider across the floor. Its position is a function of time is r + (1.2m/s)ti +
(0.7m + (0.5m/s2)t2)j, where the origin is the southwest corner of the floor. Find the average
speed of the cat between t = 0.0s and t = 4.0s - CORRECT ANSWER- 2.3 m/s
, The position of an object along the x-axis is described by the formula x = 3t 2 − 2t. Which of
the following are the correct formulas for the velocity and acceleration of the object? -
CORRECT ANSWER- v = 6t − 2, a = 6
Using the conversion factor between kilograms and pounds, 1 kg = 2.205 lb, calculate how
many pounds are in 2.00 kg. - CORRECT ANSWER- 4.41 lb
An experimental new ride at an amusement park begins by spinning patrons about a circle of
radius R with constant speed v. At some point during the ride the speed doubles and the
spokes extend, doubling the radius. After this occurs, what is the acceleration of the patrons
in terms of the original acceleration, a ? - CORRECT ANSWER- 2a
Consider a mass of 85kg lying on the ground. The coefficient of static friction between them
is us = 0.65. What is the minimum force you need to apply in order to slide the mass? -
CORRECT ANSWER- 541 N
When turning around a circle, a car is subject to a continuous force, but its speed does not
necessarily change. Why is this true? - CORRECT ANSWER- The speed is not changing, but
the direction is.
A small mass is placed on a turntable that is rotating at 45 rpm. The centripetal acceleration is
____________. - CORRECT ANSWER- greater when the mass is farther from the center of
the circle
How many significant figures are in the quantity
9.86 m/s 2? - CORRECT ANSWER- 3
Laura is listening to a record spinning at 45 rpm (revolutions per minute). When she switches
the speed selector on the record player to 33 rpm, it takes 2.7 seconds for the record player to
change to the new speed. How many revolutions does the record make during this time?
Assume that the angular acceleration of the record is constant. - CORRECT ANSWER- 1.8
A 309 g glass rolls down an incline and onto a horizontal platform where it hits a beverage
can that is laying at rest on its side. The top of the incline is 11.0 cm above the horizontal
platform. The beverage can is initially at rest and weighs 7.35 N. Which of following is the
final velocity of the glass? - CORRECT ANSWER- −0.612 m / s
