Two astronauts are working on the lunar surface to install a new telescope. The acceleration due to gravity on the moon is only 1.64 m/s2. One astronaut tosses a wrench to the other astronaut, but the speed of throw is excessive and the wrench goes over h
Its velocity and acceleration are both nonzero.
Stones are thrown horizontally, with the same initial velocity, from the tops of two different buildings, A and B. The stone from building A lands 6 times as far from the base of the building as does the stone from building B. What is the ratio of buildin
36
In uniform circular motion:
Displacement is constant.
Acceleration magnitude is constant.
Accleration direction is constant.
Acceleration and velocity are perpendicular.
Speed is constant.
Velocity is constant.
F
T
F
T
T
F
A cart of mass m can move without friction on an airtrack. Initially, it is at rest. Then, for a limited time delta T, it is pushed down the track with a constant force. Which of the following statements are true?
While the cart is pushed, it has a consta
T
F
T
If you double the force, you reach ____the final speed.
double
� If you push half as long, you reach ____ the final speed.
half
� If you use a cart with half the mass, you reach ______ the final speed.
double
If you use a cart with half the mass, you cover ____the distance during pushing.
double
The truck is driving up a mountain with a constant velocity, neglecting friction.
Ft>Fc
Ft<Fc
Ft=Fc>0
Ft=Fc=0
Correct: Ft=Fc>0
The truck is speeding up while driving up a mountain, neglecting friction.
Ft>Fc
Ft<Fc
Ft=Fc>0
Ft=Fc=0
Correct: Ft=Fc>0
The truck is driving with a constant velocity, but as it turns out, the driver of the car left the emergency brake on.
Ft>Fc
Ft<Fc
Ft=Fc>0
Ft=Fc=0
Correct: Ft=Fc>0
Choose whether each of the following statements is true or false.
An object can be moving in one direction while the net force acting on it is in another direction.
An object at rest has no forces acting on it.
In order to move a massive crate sitting on
T
F
F
T
You jump out of an airplane, and your parachute opens after a brief period of free fall. In order to slow your fall, the parachute must exert a force that is
Correct: greater than your weight.
A crate rests in the rough bed of a truck. When the truck accelerates to the left at a constant rate, what is the direction of the friction force acting on the crate? (You can assume that the crate doesn't slip in the bed of the truck.)
Correct: To the left.
What is the direction of the friction force acting on the truck, caused by the crate?
Correct: To the right.
What is the direction of the friction force acting on the truck, caused by the road?
Correct: To the left.
What is the direction of the total friction force acting on the truck?
Correct: To the left.
What is the tension of the cable?
Correct: (mHook+mLoad)*(g+a)
In the figure to the right, M2 has more mass than M1 and M1 has more mass than M3. The questions refer to the magnitudes of tensions and weights. There is friction between the horizontal plane and M2. M2 is observed to travel at a constant speed. Assume t
Equal to
False
True
Equal to
Less than
Equal to
Two blocks A and B are pushed for a certain distance along a frictionless surface. How does the magnitude of the work that A does on B compare to the magnitude of the work that B does on A?
The magnitude of the work of A on B is larger
Same (and not zero)
Correct: Same (and not zero)
How does the magnitude of the net work on A compare to the magnitude of the net work on B?
More net work on A
More net work on B
same
Correct: More net work on A
How does the magnitude of the net work on A compare to the magnitude of the work of the hand on A?
Magnitude of the work by the hand on A is larger
Magnitude of the net work on A is larger
same
Correct: Magnitude of the work by the hand on A is larger
Stan and Kyle are playing a game of "kick the baby/drop the baby" on the roof of Tom's Rhinoplasty, with Kyle's brother Ike and Ike's classmate Filmore. Kyle kicks Ike off the roof with some initial horizontal velocity. At the same instant, Stan drops Fil
They hit at the same time
A ball is thrown at a 45� angle with an initial speed v0 and reaches a maximum height of h. A second ball is thrown at the same angle with a speed of 2v0. What is the maximum height of the second ball?
4h
A ball is thrown at a 45� angle with an initial speed v0 and comes back to ground level after a time T. A second ball is thrown at the same angle with a speed of 2v0. How much time is the second ball in the air?
2T
A wheeled cart moves to the right with constant speed. As the cart moves, a spring-loaded barrel shoots a ball into the air. Where does the ball land relative to the cart?
back in the barrel
A Boeing 737 is flying at its cruising altitude on its way to Chicago. Peter is on the ground and measures the plane's speed at 500 mph. Paul is on another 737 flying next to it and asserts that the first plane is not moving at all. Meanwhile, Mary is fly
All of them are correct
A plane traveling horizontally to the right at 100 m/s flies past a helicopter that is going straight up at 20 m/s. From the helicopter's perspective, the plane's direction and speed are
A.right and up, more than 100 m/s.
B.right and up, less than 100 m/s
C
An object undergoes uniform circular motion about the origin. Which of the following vectors is constant?
A.The object's position vector.
B.The object's velocity vector.
C.The object's acceleration vector.
D.None of these vectors is constant
D
uniform circular motion
An object moving along a circular path at constant speed is undergoing uniform circular motion.
The direction of the velocity is _____to the path. The direction of the acceleration is radially __________ of the circle.
tangent, inward, toward the center
Where on the Earth's surface would an object experience the greatest radial acceleration due to the Earth's rotation?
A.At the north or south pole.
B.At 45� north or south latitude.
C.At the equator.
D.It is the same everywhere.
C
A force is a vector quantity because it has both
magnitude and direction
While ice skating, a man and his young daughter push off each other to head toward opposite ends of the rink. Which one experiences the greater force?
A.The man.
B.The daughter.
C.Neither.
C
The normal force is always ________ to the surface.
perpendicular (normal)
Lisa weighs 120 lbs. according to her bathroom scale. She brings the scale with her on an elevator on the ground floor of a tall building and stands on it. The doors close, and the elevator starts its upward journey to the 80th floor. As the rising elevat
a.greater than 120 lbs.
Once the rising elevator reaches its cruising speed, the reading on the scale is ...
a.greater than 120 lbs.
b.equal to 120 lbs.
c.less than 120 lbs., but greater than zero.
zero.
e.Not enough information is given to know.
B
As it approaches the 80th floor, the rising elevator starts to slow down, and the reading on the scale is ...
a.greater than 120 lbs.
b.equal to 120 lbs.
c.less than 120 lbs., but greater than zero.
zero.
e.Not enough information is given to know.
C
When it reaches the 80th floor, the elevator stops, but before the doors can open, the cable holding the elevator snaps. While the elevator, Lisa, and her bathroom scale are plummeting to their doom (before the emergency brake activates!), the reading on
D
Your German shepherd is relaxing on your living room floor. Based on what principle(s) can you conclude that the gravitational force on the dog and the normal force on the dog are the same magnitude but in opposite directions?
Newton's First Law.
Newton's
Newton's First Law.
Newton's Second Law.
A box sits on a flat board. You lift one end of the board, making an angle with the floor. As you increase the angle, the box will eventually begin to slide down. Why?
The component of the gravity force parallel to the plane increased.
The coefficient of
Both (a) and (c)
An object is held in place by friction on an inclined surface. The angle of inclination is increased until the object starts moving. If the surface is kept at this angle, the object...
slows down.
moves at constant speed.
speeds up.
speeds up
You are pushing a heavy refrigerator crate on its side across the floor at a constant speed. You decide to turn the crate on end, reducing by half the surface area in contact with the floor. In the new orientation, to push the crate across the floor with
equally great
The cable cars in San Francisco are pulled along their tracks by an underground steel cable that moves along at 9.5 mph. The cable is driven by large motors at a central power station and extends, via an intricate pulley arrangement, for several miles ben
10,000 N