AP Physics midterm complete
A billiard ball is moving in the x-direction at 40.0 cm/s and strikes another billiard ball moving in the y direction at 30.0 cm/s. As a result of the collision, the first ball moves at 50.0 cm/s, and the second ball stops. What is the change in kinetic energy of the system as a result of the collision.
0
an object moves 20 m east and 30 seconds and then returns to its starting point taking an additional 50 seconds. if west is chosen as a positive direction, then what sign is associated with the average velocity of the object
0 (no sign)
A 0.12-kg ball is moving at 6.0 m/s when it is hit by a bat, causing it to reverse direction and have a speed of 8.0 m/s. What is the magnitude of the change in momentum of the ball?
1.7 kg x m/s
a earth satellite is orbiting at a distance from the earth's surface equal to two earth radii. at this location, the acceleration due to gravity is what factor times the value of g at the earth's surface?
1/9
Rupel pushes a box 4.00 m by applying a 25.0 N horizontal force. What work does she do?
100 J
a room has 110 ft^2 of floor space. what is the approximate volume of the room
10^3 ft^3
an object moves at a constant velocity of 12 m/s to the southwest for an interval of 20 s. halfway through this interval what is the magnitude of its instantaneous velocity
12 m/s
What is the kinetic energy of a 0.160-kg ball thrown at 40.0 m/s (90.0 mph)?
128 J
A worker pushes a sled with a force of 40 N over a level distance of 6.0 m. If a frictional force of 16 N acts on the wheelbarrow in a direction opposite to that of the worker, hat total work is done one the wheelbarrow?
144 J
Jerome pitches a baseball of mass 0.15 kg. The ball arrives at home plate with a speed of 40 m/s and is batted straight back to Jerome with a return speed of 60 m/s. What is the magnitude of change in the ball/s momentum?
15 kg x m/s
in which of the following cases is the displacement magnitude half the distance traveled
15 steps East followed by five steps west
Samantha pushes a 60-N crate up a tamp 20.0 m in length an inclined at 10 degrees with the horizontal. What potential energy change does the crate experience?
210 J
A car wash nozzle directs a steady stream of water at 1.5 kg/s, with a speed of 20 m/s, against a car window. What force does the water exert on the glass?
30 N
an object initially moving in the negative X direction is subjected to a change in velocity in the negative Y direction. if the resulting velocity vector is drawn from the origin into which quadrant does this vector point?
3rd
A Hooke's law spring is compressed 12.0 cm from equilibrium and the potential energy stored is 36.0 J. What is the spring constant in this case?
5000 N/m
A 66-kg woman runs up a flight of stairs having a rise of 4.0 m in a time of 4.2 s. What average power did she supply?
620 W
What is the minimum amount of energy required for a 70.0-kg climber carrying a 20.0-kg pack to climb Mt. Everest, which is 8850 m high.
7.81 MJ
If both mass and velocity of a ball are doubled, the kinetic energy is increased by a factor of:
8
A 5.00 kg ball falls from a 2.00 m-high shelf. Just before hitting the floor, what will be its kinetic energy? (g = 9.80 m/s^2 an assume air resistance is negligible)
98.0 J
an observation satellite for mapping purposes is placed in a low earth orbit. in order to see the whole surface of the earth, which would be the preferred orbit
A polar orbit
The law of conservation of momentum is applicable to systems made up of objects described by which of the following?
All the above choices are valid (macroscopic, microscopic, and interacting through friction)
The work done by static friction can be:
Any of the above (positive, negative, or zero)
it is late and Carlos is sliding down the rope from his third floor window to meet his friend juan. as he slides down the rope faster and faster he becomes frightened and grabs harder on the rope, increasing the tension in the rope. as soon as the upward tension in the rope becomes equal to his weight
Carlos will continue down at a constant velocity
As an object is lowered into a deep hole in the surface of the Earth, which of the following must be assumed in regard to its potential energy?
It decreases.
Two masses m1 and m2 with m1 > m2, have momenta with equal magnitudes. How do their kinetic energies compare?
KE1 < KE2
The dimensional equivalence of the quantity "momentum" in terms of the fundamental quantities (mass, length, time) is:
MLT^-1
Two masses collide and stick together. Before the collision, one of the masses was at rest. Is there a situation in which the kinetic energy is conserved in such a collision.
No, kinetic energy is always lost in such a collision.
Two particles collide, one of them initially being at rest. Is it possible for both particls to be at rest after the collision?
No.
Which of the following is not true about potential energy?
Potential energy has direction.
an x-t graph is drawn for the ball moving in One Direction. The graph starts at the origin and at T equal six seconds the velocity of the ball is zero. we can be positive that T equals six seconds
The ball has stopped
Two blocks are released front he top of a building. One falls straight don while the other slides down a smooth ramp. If all friction is ignored, which one is moving faster when it reaches the bottom?
The both ill have the same speed
of the known planets in our solar system, the innermost is mercury. when compared to the other planets in the system, mercury has:
The greatest centripetal acceleration
A rock is moving with speed v. If the mass of the rock were tripled and the speed were reduced by v/s, which of the following statements would be true?
The kinetic energy of the rock is smaller than in the first case, but the momenta of both are the same.
which of the following expresses the principle which was Initially stated by Galileo and was later incorporated into newtons laws of motion
The natural condition for a moving object is to remain in motion
if we know an object is moving at a constant velocity we may assume
The net force acting on an object zero
assume that a reference frame is moving with the person indicated in each of the following situations. in which case is the reference frame non-inertial?
The person is skydiving and it's freefalling not yet having opened her parachute
The slope of the acceleration time curve represents
The rate of change of acceleration
In an automobile collision, how does an airbag lessen the blow to the passenger? Assume as a result of the collision, the passenger stops.
The stopping impulse is the same for either the hard objects or the airbag. Unlike the windshield or dashboard, the airbag gives some, increasing the time for the slowing process and thus decreasing the average force on the passenger.
A physics student is writing on a train traveling north. having read about inertia the student performs an experiment with the golf ball he reaches over the aisle and drops the ball from rest instead of hitting the floor directly below the student's hand it hits to the north, forward of that position. which of the following might be the cause for this to happen
The train is slowing down
a strobe photograph shows equally spaced images of a car moving along a straight road if the time intervals between images is constant. which of the following cannot be positive
The train is slowing down
a stone is thrown downward from a cliff. Take "up" to be the positive direction in which of the following statements is true about the stone
The velocity is negative, the acceleration is negative, and the speed is positive
a v-t graph is drawn for a ball moving in One Direction. the graph starts at the origin and at t=6 seconds the acceleration of the ball is zero. we know that at t=6
The velocity of the ball is not changing
baseball is thrown by a centerfielder (from shoulder level) to home plate where is caught (on the fly at shoulder level) by the catcher. at which point is the magnitude of the acceleration at a minimum at which point is the magnitude of the acceleration at a minimum. note: air resistance is negligible
acceleration is constant during the entire trajectory
when we added displacement vector to another displacement vector the result is
another displacement
Which following is dimensionally consistent with an expression yielding a value for velocity
at
Jeff throws a ball straight up, for which situation is the vertical velocity zero
at the top
A baseball catcher throws a ball vertically upward and catches it in the same spot when it returns to his mitt, at what point in the balls path does experience zero velocity and nonzero acceleration at the same time
at the top of its trajectory
A string is attached to the ceiling, at the bottom of the string, a rope of the same length as the string is attached the rope. in the rope-string system which of the following is the position of the greatest tension? Assume the rope has more mass per unit length in the string
at the top of the string
baseball is thrown by the centerfielder(from shoulder level) to home plate where is caught (on the fly at equal shoulder level) by the catcher. at what point is the ball's speed at a minimum? note: Air resistance is negligible
at the top of the trajectory
on a position-time graph, the slope of the straight line joining two points on the plotted curves are separated in time by the internal change in t, is which of the following quantities?
average velocity
if we know that a nonzero net forces acting on an object, which of the following must we assume regarding in objects condition? the object is
being accelerated
Two objects of different masses are released simultaneously from the top of a 20 m tower and fall to the ground. if air resistance is is negligible which statement best applies
both objects hit the ground at the same time
A billiard ball collides in an elastic head-on collision with a second stationary identical ball. After the collision which of the following conditions applies to the first ball?
comes to rest
At what location does an artificial earth satellite in an elliptical orbit have its lowest speed
farthest from the sun
Which of the following is an example of a nonconservative force?
friction
Which of the following best describes the property of the period of orbital revolution for an Earth satellite
greater when the orbital radius is larger
A wheel is rotated about a horizontal axle at a constant angular rate. next it is rotated in the opposite direction with the same angular rate. The acceleration a point on the top of the wheel in the second case as compared to the acceleration in the first case:
is in the same directions
in one-dimensional motion where the direction is indicated by a plus or minus sign, The average velocity of an object has which of the following properties
it can be positive, negative, or zero
in one dimensional motion the average speed of an object that moves from one place to another and then back to its original place has which of the following properties
it is positive
A car is going around a race track at a constant speed. The curves around the track have different radii. in which turn is the magnitude of the cars acceleration the greatest
it is the greatest in the turn with the smallest radius
for a point on a spinning disk in uniform circular motion, which of the following is not a constant?
it's centripetal acceleration
The unit of power, watt, is dimensionally the same as:
joule/second
The earths orbit is closest to the sun in January ann farthest from the sun in July. What is the earth moving the slowest in orbit
july
A valid unit for momentum is which of the following?
kg x m/s
The units of impulse are equivalent to:
kg x m/s
Which of the following is that form of energy associated with an object's motion?
kinetic
In a two-body collision, if the momentum of the system is conserved, then which of the following best describes the kinetic energy after the collision?
may also be conserved
The impulse experienced by a body is equivalent to its change in:
momentum
In a two-body collision, if the kinetic energy of the system is conserved, then which of the following best describes the momentum after the collision?
must also be conserved
and artificial earth satellite an elliptical orbit has its greatest centripetal acceleration when it is at what location
nearest the earth
The unit of work, joule is dimensionally the same as
newton-meter
If the momentum of an object is tripled, its kinetic energy will change by what factor?
nine
according to Kepler's law, Haleys comet circles the sun in an elliptical path with the sun at one focus of the eclipse. what is that Kepler's law indicates is at the other focus of the eclipse
nothing
baseball is moving in the air along the customary parabola. ignoring air drag where is the force on the baseball zero
nowhere
Which of the following is that form of energy associated with an object's location in a conservative field?
potential
The rate at which work is done is equivalent to which of the following?
power
The value of an objects acceleration may be characterized in equivalent words by which of the following
rate of change of velocity
Changing a positive direction in a reference frame to the opposite direction does not change the side of which of the following quantities
speed
which of the following is not a vector quantity
temperature
about moves through the water in a river at a speed of 8 m/s relative to the water. The boat makes the trip downstream and then makes the return upstream to the original starting place. which trip takes less time?
the downstream trip
I an inelastic collision between two objects with unequal masses:
the momentum of one will increase by the amount the momentum of the other decreases
Two objects, one less massive than the other, collide elastically and bounce back after the collision. If the two originally had velocities that were equal I size by opposite in direction, then which one will be moving slower after the collision.
the more massive one
two objects are in circular orbits of different radii around the sun. which object has the lowest orbital speed
the one farthest from the sun
When a collision is completely inelastic, then:
the participants stick together
what is (are) the location(s) of the low tide(s) on the earth caused by the gravitation of the moon? give the location(s) relative to the line through the Earth's and Moon's centers, line EM
the points on the Earth's surface perpendicular to EM at the Earths center
A billiard ball collides in an elastic head-on collision with a second identical ball. What is the kinetic energy of the system after the collision compared to that before the collision?
the same as it started
A moderate force will break an egg. However, an egg dropped o the road usually breaks while one dropped in the grass usually doesn't break. This is because for the egg dropped on the grass:
the time interval for stopping is greater
In a system with two moving objects, when a collision occurs between the objects:
the total momentum is always conserved
The statement by Newton that for every action there is an opposite but equal reaction is regarded as which of the laws of motion
third
when it comes to tides, high and low, what is the usual situation in the ocean's coast?
two high tides and two low tides a day.
consider a point on a bicycle tire that is momentarily in contact with the ground as the bicycle rolls across the ground with constant speed. The direction for the acceleration for this point at that moment is
upward
which is not dimensionally correct
v= a/t
displacement is which of the following types of quantities
vector
The quantity of work equal to one joule is also equivalent to which of the following?
watt x s
in the terminology "a 500- N block" the "500- N" refers to the block's
weight
A change in physical quantity w, having initial value wi, and final value wf is given by which of the following
wf-wi
A very light cart holding 300-N box is moved at a constant velocity across a 15-m level surface. What is the total work done in the process?
zero
As the car moves forward on a level Road at a constant velocity the total force acting on the tires is
zero
A ball with original momentum +2.0 kg x m/s hits a wall and bounces straight back without losing any kinetic energy. The change in momentum of the ball is:
-4.0 kg x m/s
The area under the force-displacement curve represents:
Work