PHYS STRAIGHTERLINE QUESTIONS AND
ANSWERS ELABORATIONS!!
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?
answers: 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?
answers: 5
Which of the following is involved in uniform circular motion?
answers: 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?
answers: Toa > To
How can you calculate the magnitude of a vector using scalar products?
answers: 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?
,answers: 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.
answers: false
Which of the following statements concerning friction between the surfaces of two
objects is correct?
answers: 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.
answers: 606 m
Which of the following statements concerning friction is incorrect?
answers: 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?
answers: 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?
answers: 42°
A vector is quantity that requires both magnitude and ________.
,answers: 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?
answers: 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.)
answers: 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?
answers: 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?
answers: 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
answers: 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?
answers: 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.
answers: 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 ?
answers: 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?
answers: 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?
answers: 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 ____________.
answers: greater when the mass is farther from the center of the circle
How many significant figures are in the quantity
ANSWERS ELABORATIONS!!
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?
answers: 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?
answers: 5
Which of the following is involved in uniform circular motion?
answers: 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?
answers: Toa > To
How can you calculate the magnitude of a vector using scalar products?
answers: 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?
,answers: 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.
answers: false
Which of the following statements concerning friction between the surfaces of two
objects is correct?
answers: 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.
answers: 606 m
Which of the following statements concerning friction is incorrect?
answers: 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?
answers: 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?
answers: 42°
A vector is quantity that requires both magnitude and ________.
,answers: 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?
answers: 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.)
answers: 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?
answers: 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?
answers: 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
answers: 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?
answers: 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.
answers: 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 ?
answers: 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?
answers: 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?
answers: 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 ____________.
answers: greater when the mass is farther from the center of the circle
How many significant figures are in the quantity
