Conceptual Physics Final
The windshield of your car traveling at 100 km/hr strikes a hapless bug with a force that spatters it. The force of impact is greater on the
...is the same on each
The net force on a 1-N apple held above your head is
0 N
When a 10-N falling body encounters 10 N of air resistance the net force on the body is
0 N
If a falling object falls 8 meters in one second of fall, and 8 meters again during the second second of fall, and 8 meters again during the third second, its acceleration is
0 meters per second squared
A meter stick is balanced horizontally at its center of gravity. A 10 newton weight hangs .10 meters from the support and produces a torque of
1 Newton-meter
Two people engage in a tug-of-war with each other and each pulls with a force of 400 n. The tension in the rope is then
400 N
Still ignoring air resistance, how high is the ball at its highest point?
45 m
About how many octaves are present in a hearing range from 375 hertz to 12000 hertz?
5
An object is pulled northward with a force of 10 N and southward with a force of 15 N. The net force on the object is
5 N
If an explosion occurs 1.7 kilometers away, the time it will take for the second sound to reach you (assuming sound travels at 340 m/s) is about
5 seconds
You're driving down the highway and a bug spatters into your windshield. Which undergoes the greater change in momentum during the time of contact?
Both the same
When a rifle is fired it recoils so both the bullet and rifle are set in motion. The gun and bullet acquire equal
But opposite amounts of momentum
You sound a 1056 hertz tuning fork at the same time that a note on a piano keyboard is hit and you hear two beats per second. The frequency of the string must be
Can't really say
If bullets are fired from an airplane in the forward direction of its motion, the momentum of the airplane will be
Decreased
According to Newton's universal law of gravitation, as the distance between two bodies increases, the gravitational force between the two bodies
Decreases
Consider an open freight car rolling friction free along a horizontal railroad track in a pouring rain that falls vertically. As water accumulates in the car, its speed
Decreases
Suppose a simple pendulum is suspended in an elevator. If the elevator is accelerating upward, the period of the pendulum
Decreases
A cable car rolls along a track with considerable momentum. If it rolls twice as fast its momentum will be
Doubled
According to the impulse-momentum equation Ft = change in (mv), a person will suffer less injury falling on a wooden floor which "gives" than on a more rigid cement floor. The "F" in the above equation stands for the force exerted on the
Either of these
An object at rest may have
Energy
A baseball bat hits a ball with a force of 1000 N. The bat slows down because the ball exerts a resisting force against the bat of
Exactly 1000 N
Galileo demonstrated that a heavy and light body dropped at the same instant
Fall at almost exactly the same rate
If you use large diameter tires on your car, compared to your speedometer reading, you are really traveling
Faster
Newton's second law states that
Force is proportional to mass multiplied by acceleration (F=ma)
When a source of sound approaches you, there is an increase in the sound's
Frequency
Your weight is measurement of
Gravitational attraction
If a freely falling body were somehow equipped with an odometer to measure the distance traveled, then with each succeeding second the amount of distance traveled would be
Greater than the second before
The greater the rotational rate of a space habitat, the
Greater the effective weight of its inhabitants
An object is raised above the ground gaining a certain amount of potential energy. If the same object is raised twice as high, it will
Have twice as much potential energy
Sound waves cannot travel in which of the following:
In a vacuum
If Earth rotated more slowly about its axis, your weight would
Increase
A rock is thrown vertically into the air. At the very top of its trajectory the net force on it is
Its weight
Two pool balls roll toward each other. Each is moving at 10 km/hr. After bouncing they roll apart, each moving at 15 km/hr. This collision violates conservation of
Kinetic energy
Xenon has atomic number 54; krypton has atomic number 36. In which medium would sound travel fastest?
Krypton gas
Compared to its weight on earth, the weight of a 10-kg package on the moon would be
Less
A ball is projected into the air with 100 joules of kinetic energy, which is transformed to gravitational potential energy at the top of its trajectory. When it returns to its original level after encountering air resistance its kinetic energy is
Less than 100 joules
If the polar icecaps melted, the resulting water would spread over the entire Earth. This new mass distribution would tend to make the length of a day
Longer
A moving body on which no forces are acting will continue to move with constant
Momentum
Two objects, A and B, have the same size and shape, but A is twice as heavy as B. When they are dropped simultaneously from a tower, they reach the ground at the same time, but A has a higher
Momentum
A golf ball moving forward with 1 unit of momentum strikes a heavy bowling ball that is initially at rest and free to move. After the golf ball bounces backward, the bowling ball is set in motion with a momentum that must be
More than 1 unit
According to Newton's laws of motion, if we could somehow remove the sun and gravitational force between a planet and the sun, the planet would
Move away from the sun in a straight line
The faster-moving horse on a merry-go-round is located
Near the outside
An astronaut on another planet drops a 1-kg rock from rest and finds that it falls a vertical distance of 4 meters in one second. On this planet the rock has a weight of
None of the other answers is correct
A weight suspended from a spring is seen to bob up and down over a distance of 1 meter in two seconds. Its frequency is
One half hertz
The kinetic energy of a satellite in elliptical orbit about the earth is greatest at the
Perigee (nearest point)
A cable car rolls along a track with considerable momentum. If it rolls twice as fast and has twice the mass its momentum will be
Quadrupled
Which will be the slowest in rolling down a hill? (Ring, disk, ball)
Ring
"Centrifugal force" is an apparent reality to observers in a frame of reference which is
Rotating
A child is observed to swing back and forth with regularity on a playground swing. If she stand rather than sits, the time for a to and fro swing is
Shortened
A ball is dropped. According to Newton's third law, the action force is the earth pulling on the ball, and the reaction is
The ball pulling on the earth
Skaters spin faster by pulling in their arms. This illustrates
The conservation of angular momentum
For which angle does the Resultant of the vector A and vector B have the greatest magnitude (length)?
The most narrow one (see test 1 question 44)
Compared to its mass on earth, the mass of a body on the moon would be
The same
If a force of 1 N accelerates a mass of 1 kg at the rate of 1 meter per second squared, then the acceleration of a mass of 2 kg acted upon by a force of 2 N is
The same
What is the mass of a 10-kg object on Mars compared to Earth?
The same
There are about as many atoms of air in our lungs at any moment as there are breaths of air in the atmosphere of
The whole world
An object thrown into the air rotates about its
center of gravity
If an object has kinetic energy, then it also must have
momentum
Two identical freight cars roll freely towards each other on a level track. One car rolls at 3 m/s to the right and the other car rolls at 1 m/s to the left. After the cars collide, they couple and roll together toward the right with a speed of
1 m/s
Two identical freight cars roll freely towards each other on a level track. One car rolls at 2 m/s to the right and the other car rolls at 1 m/s to the left. After the cars collide, they couple and roll together toward the right with a speed of
1/2 m/s
If the force of friction on a sliding body is 10 Newtons, then the force needed to maintain constant velocity is
10 N
A tuning fork of frequency 200 hertz will resonate if a sound wave incident on it has a frequency of
100 Hertz
Suppose you sound a 1053 hertz tuning fork at the same time that you hit a note on a piano keyboard and hear two beats per second. You tighten the piano string very slightly and then hear three beats per second. The frequency of the string is now
1056 hertz
To determine the acceleration due to gravity on another planet you observe that an object released from rest requires one second to fall a distance of 6 meters, whereupon you conclude the acceleration due to gravity is
12 meters per second squared
Forces of 3.0 N and 4.0 N act at right angles on a block of mass of 20 kg. What is the acceleration of the block?
2.5 m/s^2
If a freely falling body were somehow equipped with a speed-ometer on a planet where the acceleration due to gravity were 20 meters per second squared, then its speed reading each second would increase by
20 m/s
A ukulele string 0.25 m long has a fundamental frequency of 440 hertz. The speed of the waves on the string will be
220 m/s
A car and occupant traveling at 80 km/hr hits a tree and comes to a stop. If the time to come to a stop is 0.1 seconds, the magnitude of the acceleration that the occupant under-goes is about
220 meters squared
A space habitat designed for earth-normal gravity and a rotational rate of 2 RPM's should have a radius of
225 m
What is the resultant of the pair of velocities 100 km/h north and 75 km/h south?
25 km/h northward
You toss a ball straight up in the air with an initial speed of 30 m/s. Ignoring air resistance, how long before it gets to its highest point?
3 Seconds
Radio waves travel at the speed of light, 300,000 km/s. The wavelength of a radio wave received at 100 megahertz is
3 meters
Two identical freight cars roll freely towards each other on a level track. One car rolls at 2 m/s to the right and the other car rolls at 1 m/s to the right. After the cars collide, they couple and roll together toward the right with a speed of
3/2 m/s
A grocery bag can withstand 300 N of force before it rips apart. How many kilograms of apples can it safely hold?
30 kg
A 2000-kg car experiences a braking force of 10,000 Newtons and skids to a stop in 6 seconds. The speed of the car just before the brakes were applied must have been
30 m/s
When a parachutist who weighs 800 N opens his chute and experiences an initial air resistance force of 500 N, the net force on the parachutist is
300 N downward
A 1000-kg automobile enters a freeway on-ramp at 20 m/s and accelerates uniformly up to 40 m/s in a time of 10 seconds, during which the automobile travels a distance of
300 m
The magnitude of acceleration of an automobile in a full skid on dry pavement is about 1/2 g. If you are driving at 80 km/hr and slam on your brakes, the time required to skid to a stop is about
4 1/2 seconds
When two people, once twice as massive as the other, attempt a tug-of-war with a 12-meter rope on frictionless ice, they meet. The heavier person will have slid a distance of
4 meters
Gravity on the surface of mars is 2/5 as strong as gravity on Earth. What is the weight of a 10-kg object on mars?
40 N
A 10-kilogram block is set sliding with an initial velocity of 10 m/s and slides 10 meters across a horizontal surface in 2 seconds whereupon it comes to rest. The friction force acting on the block must have been about
50 N
A person is attracted towards the center of the earth by a gravitational force of 500 N. The force which the earth is attracted towards the person is
500 N
A skydiver who weighs 500 N reaches a terminal velocity of about 90 kilometers per hour. The air resistance she encounters in fall is
500 N
A diver who weighs 500 N steps off a diving board that is 10 meters above the water. She hits the water with a kinetic energy of
5000 Joules
When a 10-N falling body encounters 4-N of air resistance the net force on the body is
6 N
A plant pot falls from a ledge and hits the ground 180 meters below. Ignoring air resistance, the speed with which it hits the ground is about
60 m/s
How deep is a mine shaft if it takes 6 seconds for a stone to fall to the bottom?
About 180 meters
The rate of change of the velocity of a body with time is called the body's
Acceleration
Whenever the net force acting on an object of constant mass is doubled, then the acceleration is
Always doubled
If a body experience a net torque, this implies that it experiences
Angular acceleration
A cable car rolls along a track with considerable momentum. If it rolls twice as fast and has half the mass its momentum will be
As it was in the first place
Together in a vacuum, the heavier object will fall
At the same speed as the lighter object
Someone standing at the edge of a cliff throws a ball straight up and another straight down with the same initial speed. If air resistance is negligible, the ball to hit the ground below with the greatest speed will be the one initially thrown
Both the same
A Doppler effect occurs when a source of sound moves
Toward you
As you stand on the surface of the turning earth, you are moving in a circle; therefore, there must be a tiny unbalanced force of some kind acting on you. True or false?
True
Sound waves can interfere with one another in such a way that no sound may result. True or false?
True
The gravitational force of the earth on the moon must be just as strong as the force of the moon on the earth. True or False?
True
A constant net force on a body of constant mass produces
Uniform acceleration
If an object is in free fall its
Velocity increases
A push on a one kilogram brick accelerates a 10 kilogram brick, one would have to push
With 10 times as much force
