physics 101 midterm 1 study
If you push an object twice as far while applying the same force, you do
twice as much work
When a rock thrown straight upwards gets to the exact top of its path, its
velocity is zero and its acceleration is about 10 meters per second per second.
The force required to maintain an object at a constant velocity in free space is equal to
zero
A skydiver jumps from a high-flying plane. As her velocity of fall increases, her acceleration
decreases
The two measurements necessary for calculating average speed are
distance and time
A bullet is dropped from the top of the Empire State Building while another bullet is fired downward from the same location. Neglecting air resistance, the acceleration of
each bullet is 9.8 meters per second per second
a prize fighter ungloved fist can do more damage to a jaw than a gloved fist. The reason for this is that the ungloved fist
exerts a shower impulse to the jaw
The force that accelerates a rocket in outer space is exerted on the rocket by the
exhaust gas
The total momentum of a flock of identical birds could be zero only if the birds are
flying in different directions
The newton is a unit of
force
A coconut and a feather fall from a tree through the air to the ground below. The amount of air-resistance force is
greater on the coconut
If an object falling freely were somehow equipped with an odometer to measure the distance it travels, then the amount of distance it travels each succeeding second would be
greater than the second before
An object following a straight - line path at constant speed
has zero acceleration
A skydiver's terminal velocity will be greatest if she falls
head first
A bullet is fired from a gun. The speed of the bullet will be about the same as the speed of the recoiling gun
if the mass of the bullet equals the mass of the gun
Compared to the force that brings a small car to a stop, the force required to bring a heavy truck to a stop
impossible to determine without additional information
If a non-rotating object has no acceleration, then we can say for certain that it is
in a mechanical equilibrium
padded dashboards in cars are safer in an accident that nonpadded ones because an occupant hitting the dash has
increased time of impact
If an object's mass is decreasing while a constant force is applied to the object, the acceleration
increases
In each second of fall, the distance a freely falling object will fall is
increasing
The force exerted by the road on each tire of an accelerating car
is less than the combined force of all four tires on the road.
A lightweight feather slides off a table and falls through the air until it reaches the floor. During the time of its fall, its acceleration
is sometimes zero
A skydiver steps from a helicopter and falls for a few seconds until he reaches his terminal velocity. Thereafter, until he opens his parachute, his acceleration
is zero
A ball thrown straight upward takes 10 seconds to go up and return to the ground. Because of air resistance, the time taken for the ball just to go up is
less than 5 s
An object may have potential energy because of its
location
A force is a vector quantity because it has both
magnitude and direction
A kilogram is a measure of an object's
mass
If the speed of a moving object doubles, which of the following also doubles?
momentum
Two objects have the same size and shape, but one is much heavier than the other. When they are dropped simultaneously from a tower, they reach the ground at the same time, but the heaver one has a greater
momentum
A golf ball moving forward with 1 unit of momentum strikes and bounces backward off a heavy bowling ball that is initially at rest and free to move. The bowling ball is set in motion with a momentum of
more than 1 unit
If a monkey floating in outer space throws his hat away, the hat and the monkey will both
move away from each other, but at different speeds
An astronaut, floating alone in outer space, throws a baseball. If the ball floats away at a speed of 20 m/s, the astronaut will
move in the opposite direction, but at a lower speed
An object that has kinetic energy must be
moving
If you push for a half hour or a whole hour against a stationary wall,
no work is done in either case
A large heavy truck and a small baby carriage roll down a hill, neglecting friction, at the bottom of the hill, the baby carriage will have a greater
none of these
A skydiver falls toward the Earth. The attraction of the Earth on the diver pulls the diver down. What is the reaction to this force?
none of these
Compared to a 1-kg block of solid iron, a 2-kg block of solid iron has the same
none of these a) mass b) volume c) weight
An object at rest may also have
potential energy
A rifle recoils when firing a bullet. The speed of the rifle's recoil is small because the
rifle has much more mass than the bullet
Two factors that greatly affect air resistance on falling objects are the
size and speed of the object
Galileo's use of inclined planes allowed him to effectively
slow down the acceleration of free fall
Which requires the most amount of work by the brakes of a car?
slowing down from 100 km/h to 70 km/h
Which of the following is not a vector quantity?
speed
Compared to falling on a stone floor, a wine glass may not break when it falls on a carpeted floor because the
stopping time is shorter on the carpet
A ball rolling down an incline has its maximum kinetic energy at
the bottom
A block of ice sliding down an incline has its maximum speed at
the bottom
It is correct to say that impulse is equal to
the change in momentum
If a more horizontal force is applied to a sliding object than is needed to maintain a constant velocity,
the object accelerates in the direction of the applied force
If less horizontal force is applied to a sliding object than is needed to maintain a constant velocity,
the object eventually slides to a stop
The attraction of a person's body toward the Earth is called weight. The reaction to this force is
the person's body pulling on the Earth
A feather and a coin will have equal acceleration when falling in a vacuum because
the ratio of each object's weight to its mass is the same
A ball is thrown upwards and returns to the same position. Compared with its original speed after release, its speed when its returns is about
the same
Both a 50-kg sack is lifted 2 meters from the ground and a 25-kg is lifted 4 meters in the same time. The power expended in raising the 50-kg is
the same
After rolling halfway down an incline a marble's kinetic energy is
the same as its potential energy
A automobile and a baby carriage traveling at the same speed collide head-on. The impact force is
the same for both
A car traveling a 100 km/hr strikes an unfortunate bug and splatters it. The force of impact is
the same for both
Suppose that a tiny gun made of a strong but very light material fired a bullet that is more massive than the gun itself. For such a weapon
the target would be safer than the shooter
The ball rolling down an incline has its maximum potential energy at
the top
The Earth pulls on the moon. Similarly the moon pulls on the Earth, evidence that
these two pulls comprise an action-reaction pair
The difference between impulse and impact force involves the
time the force acts
An object is propelled along a straight-line path by a force. If the net force were doubled, the object's acceleration would be
twice as much
A 1000-kg car and a 2000-kg car are hoisted the same distance. Raising the more massive car requires
twice as much work
If you push an object a given distance, while applying twice the force, you do
twice as much work
A sack of potatoes weighing 200N falls from an airplane. As the velocity of fall increases, air resistance also increases. When air resistance equals 200 N, the sack's acceleration in meters per second per second is
0
An object covers a distance of 8 meters in the first second of travel, another 8 meters again during the third second. Its acceleration in meters per second per second is approximately
0
Two billiard balls having the same mass and speed roll toward each other. What is their combined momentum after they meet?
0
a 1-kg chunk of putty moving at 1 m/s collides with and sticks to a 5-kg bowling ball initially at rest. The bowling ball and putty move with a momentum of
1 kg m/s
A piece of putty moving with 1 unit of momentum strikes and sticks to a heavy bowling ball that is initially at rest. After the putty sticks to the ball, both move with a combined momentum of
1 unit
A 10-kg brick and a 1-kg book are dropped in a vacuum. The force of gravity on the 10-kg brick is
10 times as much
A jumbo jet has a mass of 100,000 kg. The thrust for each of its four engines is 50,000N. What is the jet's acceleration in meters per second per second when taking off?
2
A man weighing 800 n stands at rest on two bathroom scales so that his weight is distributed evenly over both scales. The reading on each scale is
400 N
When a woman stands at rest with both feet on a scale, it reads 500 N. When she gently lifts one foot, the scale reads
500 N
A block is dragged without acceleration in a straight-line path across a level surface by a force of 6 N. What is the force of friction between the block and the surface?
6 N
The impulse-momentum relationship is a direct result of
Newton's 2nd law
The conservation of momentum is most closely related to
Newton's 3rd law
A flower pot of mass m falls from rest to the ground below, a distance h.
The KE of the pot when it hits the ground is proportional to h.
An object lifted 10 m gains 200 J of PE. If the same object is lifted 20 m, its PE gain is
Twice as much
A Mack truck and a Volkswagen traveling at the same speed have a head-on collision. The vehicle that undergoes the greatest change in velocity will be the
Volkswagen
Which of the following has the largest momentum relative to the Earth?
a pickup truck speeding along a highway
A ball is thrown upwards. Neglecting air resistance what initial upward speed does the ball need to remain in the air for a total time of 10 seconds?
about 50 m/s
Disregarding air resistance, objects fall with constant
acceleration
If an object of constant mass experiences a constant net force, it will have a constant
acceleration
A feather and a coin dropped in a vacuum fall with equal
accelerations
A heavy and a light object released from the same height in a vacuum have equal
accelerations
The force on an apple hitting the ground depends upon
all of these
Which as zero acceleration? An object
all of these a) at rest b) moving at constant velocity c) in mechanical equilibrium
Compared to a 1-kg block of solid iron, a 2-kg black of solid iron has twice as much
all of these a) inertia b) mass c) volume
Strictly speaking, more fuel is consumed by your car if an air conditioner, headlights or even a radio is turned on. This statement is
almost always true
A hydraulic press, like a wheel and axle, is capable of multiplying force input
always true
Which has the greater mass?
an automobile battery
When you relax at rest with your left foot in one bathroom and your right foot on a similar scale, each of the scales will
any of the above may be correct
Hang from a pair of gym, rings and the upward support forces of the rings will always
ass up to equal your weight
Neglecting friction, a large block of ice and a small block of ice start sliding down an incline together. The heavier block will get to the bottom
at the same time as the light block
Neglecting friction, a large block of ice and a small block of ice start sliding down an incline together. The heavier clock will get to the bottom
at the same time as the light block
A heavy object and a light object are dropped at the same time from a rest in a vacuum. The heavier object reaches the ground
at the same time as the lighter object
Arnold Strongman and Suzie Small each pull very hard on opposite ends of a massless rope in a tug-of-war. The greater force on the rope is exerted by
both the same, interestingly enough
If an object moves with constant acceleration, its velocity must
change by the same amount each second
Suppose a particle is being accelerated through space by a 10 - N force. Suddenly the particle encounters a second force of 10 n in the opposite direction from the first force. The particle with both forces acting on it
continues at the speed it had when it encountered the second force
