Physics multiple choice

The same tow truck exerts a force of 2000 N on a very rusty old car and moves it at constant velocity. How much friction is opposing the tow truck's pull? A. 500 N B. 1000 N C. 2000 N D. 3000 N E. None of the above

c

A ball is thrown straight up into the air. At the top of its path the instantaneous speed is A. 0 m/s B. 5 m/s C. 10 m/s D. 20 m/s E. Depends on the situation

A

A ball with mass 2.0 kg is dropped from 3-m. Its momentum just as it strikes the ground is: A. 15 kgm/s B. 30 kgm/s C. 40 kgm/s D. 60 kgm/s E. 1.8 kgm/s

A

A constant 6.0 N force acts for 4.0 seconds on a 12 kg object. What is the object's change in velocity? A. 2.0 m/s B. 12 m/s C. 18 m/s D. 288 m/s

A

A low-orbit satellite of Earth has a speed of 8000 m/s. A satellite at a higher altitude would have a velocity which was A. Smaller than 8000 m/s B. Larger than 8000 m/s C. Equal to 8000 m/s D. Impossible to determine with the given information

A

A scalar is a quantity that has only A. Magnitude B. Time C. Direction . Color

A

A turntable turns at a rotation rate of 72 RPM. Compared with a ladybug sitting near the center, a ladybug sitting at the edge of the turntable has A. Larger linear velocity B. A smaller linear velocity C. The same line linear velocity D. More information needed

A

An object that has kinetic energy must be A. moving B. Falling C. Elevated D. At rest E. None of the above

A

An object travels 8 meters in the first second of travel, then 8 meters again in the second second of travel, and finally 8 meters again in the third second of travel! It's acceleration is A. 0 m/s/s B. 8 m/s/s C. 16 m/s/s D. 32 m/s/s E. None of the above

A

Energy is changed from one form to another with no net loss or gain. A. Always true B. Sometimes true C. Always false

A

Suppose a car moves in a straight line and steadily increases its speed. It moves from 35 km/hr to 40 km/hr in the first second and from 40 km/hr to 45 km/hr in the next second. What is the car's acceleration? A. 5 km/h/s B. 10 km/h/s C. 35 km/h/s D. 40 km/h/s E. 45 km/h/s

A

Suppose a moving car has 200 J of kinetic energy. If the car's speed doubles, how much kinetic energy would it have? A. 8000 J B. 6000 J C. 4000 J D. 2000 J E. 1000 J

A

Suppose the gravitational force between two massive spheres is 10N. If the distance between the spheres is cut in half, then the force between them would be A. 40 N B. 20 N C. 5 N D. 2.5 N

A

When you look at the speedometer in a moving car, you can see the car's A. Instantaneous speed B. Average speed C. Instantaneous acceleration D. Average acceleration E. Average distance traveled

A

A Boulder is raised above the ground so that it's potential energy is 200J. Then it is dropped. Just before it hits the ground, it's kinetic energy is: A. 400J B. 200J C. 100J D. 0J

B

A ball is thrown into the air at some angle. At the very top of the balls path, it's velocity is A. Entirely vertical B. Entirely horizontal C. Both vertical and horizontal D. More information is needed

B

A ball moves at 4.0 m/s and has a momentum of 48 kg m/s. What is the ball's mass? A. 4.0 kg B. 12 kg C. 48 kg D. 192 kg E. None of the above

B

A car acceleration at 2 m/s/s. Assuming the car starts from rest, how much time does it need t accelerate to a speed of 30 m/s? A. 2 seconds B. 15 seconds C. 30 seconds D. 60 seconds E. None of the above

B

Acceleration is defined as the change in A. Distance divided by the time interval B. Velocity divided by the time interval C. Time it takes to move from one speed to another speed D. Time it takes to move from one place to another E. Velocity of an object

B

Acceleration is defined as the change in A. Distance divided by the time interval B. Velocity divided by the time interval C. Time it takes to move from one speed to another speed D. Velocity of an object

B

An object following a straight line path at constant speed: A. Has a net force acting on it in the direction of motion B. Has a zero acceleration C. Must be moving in a vacuum D. Has no forces acting on it E. None of the above

B

How does the acceleration of an object change in relation to mass if a constant force is acting? A. Directly proportional B. Indirectly (inversely) proportional C. Acceleration does not depend on mass

B

How much farther will the car traveling at 100 km/hr skid when the brakes are locked as compared to the same car traveling at 50 km/hr? A. Fives times as far B. Four times as far C. Three times as far D. Two times as far E. The same distance

B

How much more kinetic energy does a car traveling at 100 Km/hr have compared to the same traveling at 50 km/hr? A: five times B: four times C. Three times D. Two times E. The same kinetic energy

B

How much work is done on a 50 N rock that you lift up 10 meters? A. 5000 J B. 500 J C. 50 J D. 10 J E. 0 J

B

If you lift one load up two stories, how much work do you do compared to lifting one load up only one story? A. Four times the work B. Twice the work C. The same work D. Half the work E. One quarter the work

B

Newton reasoned that the gravitational attraction between Earth and the moon must be A. Directly proportional to the square of the distance between them B. Inversely proportional to the square of the distance between them C. The same at all distances D. Independent of distance

B

Suppose a long jumper has a 'hang time' of 1.0 seconds. That means the jumpers feet are off the ground for 1.0 seconds. How high does the jumper jump? A. 1.0 meter B. 1.25 meters C. 3.0 meters D. 5.0 meters

B

The components of a vector oriented at 45 degrees with the horizontal are __________________ than the length of the original vector. A. Greater B. Smaller C. Equal D. Zero

B

The mass of a dog that weighs 100N is about A. 1kg B. 10kg C. 100kg D. 1000kg E. None of the above

B

The slope of a displacement vs time graph gives A. Speed B. Velocity C. Average speed D. Total distance traveled

B

The y-intercept of a velocity vs time graph gives A. Starting speed B. Starting velocity C. Acceleration D. Total change in position

B

A moving freight car runs into an identical car at rest on the track. The cars couple together. Compared to the velocity of the first car before the collision, the velocity of the combined cars after the collision is A. Twice as large B. The same C. One half as large D. Zero E. More information is needed

C

A rifle recoils from firing a bullet. The speed of the rifle's recoil is small because the A. Force against the rifle is relatively small B. Impulse on the rifle is less than the impulse on the bullet C. Rifle has lots more mass than the bullet D. Momentum of the rifle is unchanged E. None of the above

C

A small car meshes to a large truck in a head on collision. Which of the following statements about the magnitude of the force is true? A. The force of the truck on the car is greater B. The force of the car on the truck is greater C. The car and truck experience the same average force D. It's impossible to tell, masses and velocity aren't known

C

A tennis ball and a solid steel ball the same size are dropped at the same time. In the absence of air resistance, which ball has the greatest acceleration? A. The tennis ball B. The steel ball C. The same acceleration

C

A tennis ball and a solid steel ball the same size are dropped at the same time. In the absence of air resistance, which ball hits the group first? A. The tennis ball B. The steel ball C. The same time

C

A tow truck exerts a force of 3000N on a car, accelerating the car at 2 m/s/s. What is the mass of the car? A. 500 Kg B. 1000 Kg C. 1500 Kg D. 3000 Kg E. None of the above

C

If Nellie Newton pushes an object with twice the force for twice the distance, she does: A. The same work B. Twice the work C. Four times the work D. Eight times the work

C

If an object is in uniform circular motion and suddenly the force disappears, the object would A. Continue to move in a curved path B. Move in a path that points away from the center of the circle C. Move in a path that is tangent to the circle D. Stop moving

C

If you pull on a crate with a force of 150 N and the crate doesn't move, the friction force must be 150 N. Now if you pull with 250 N so the crate slides with constant velocity, the friction force is A. 150 N B. More than 150 N but less than 250 N C. 250 N D. More than 250 N

C

In order to catch a ball, a baseball player moves his or her hand backward in the direction of the ball's motion. Doing this reduces the force of impact on the player's hand because A. The velocity of impact is reduced B. The momentum of impact is reduced C. The time of impact is increased D. The time of impact is decreased E. None of the above

C

In the absence of air resistance, the vertical component of a projectile's velocity doesn't change as the projectile moves. A. Always true B. Sometimes true C. Never true

C

Newton's law of inertia applies to: A. Moving object B. Objects at rest C. Both moving and non-moving objects D. Only little Debbie snack cakes

C

Suppose a cart is being moved by a force. If suddenly a load is dumped into the cart so that the cart's mass doubles, what happens to the cart's acceleration? A. It quadruples B. It doubles C. It halves D. It quarters

C

Ten seconds after starting from rest, a freely falling object will have a speed of about A. 10 m/s B. 50 m/s C. 100 m/s D. 500 m/s E. More than 500 m/s

C

The slope of a velocity vs time graph gives A. starting speed B. Starting velocity C. Acceleration D. Total change in position

C

The vertical motion of an object dropped fro ma 100 meter cliff is ____________________ the vertical motion of an object which is projected out horizontally from the 100 meter cliff. A. Greater than B. Smaller than C. The same as D. None of the above

C

What is the momentum of a 200 kg truck traveling at 20 m/s? A. 100 kgm/s B. 20,000 kgm/s C. 4,000 kgm/s D. 40,000 kgm/s

C

When something falls to the ground, it accelerates. This acceleration is called the acceleration due to gravity and is symbolized by the letter g. What is the value of g on the Earth's surface? A. 0 m/s/s B. About 5 m/s/s C. About 10 m/s/s D. About 20 m/s/s E. About 50 m/s/s

C

Which are units of impulse and/or momentum? A. Nm B. N/s C. Ns D. N/m

C

A 10 N force and a 20 N force act on an object in opposite directions. What is the net force acting on the object? A. 40N B. 30N C. 20N D. 10N

D

A sheet of paper can be withdrawn from under a heavy milk bottle without toppling the bottle if the paper is jerked out quickly. The reason this can be done is that A. The milk bottle has very little weight B. There is an action-reaction pairing C. Gravity pulls very hard on the milk bottle D. The milk bottle has inertia E. None of the above

D

Friction: A. Acts in a direction that opposes the notion of an object B. Comes from microscopic bumps that act as obstructions to the object's motion C. Is the same name given to the force acting between surfaces sliding past one another D. All of the above E. None of the above

D

How much force is needed to accelerate a 2 kg physics book to an acceleration of 6 m/s/s? A. 36 N B. 12 N C. 3 N D. .33 N E. 0 N

D

If you were to weigh yourself in an elevator that is in free fall, compared to your ordinary weight, you would weigh A. More B. The same C. Less D. Zero

D

Issac Newton is known for A. Theorizing three laws of motion B. Inventing calculus C. Realizing that projectile motion is the same as orbital motion D. All of the above

D

Suppose an object is in free fall. Each second the object falls A. With the same average speed B. With the same instantaneous speed C. The same distance as before D. A larger distance as before E. None of the above

D

The acceleration produced by a net force is A. Directly proportional to the magnitude of the force B. In the same direction as the net force C. Inversely proportional to the mass of the object D. All of the above

D

The gravitational force between two massive spheres is 10 Newtons. If the distance between the spheres is doubled, what is the force between them? A. 40 N B. 20 N C. 5 N D. 2.5 N

D

The value of the acceleration due to gravity, 'g', on Earth A. Depends on the radius of Earth B. Depends on the mass of Earth C. Is different on other plants D. All of the above

D

Which has more mass: a kilogram of feathers, a kilogram of water or a kilogram of iron: A. The feathers B. The water C. The iron D. They all have the same mass

D

A ball is thrown straight up into the air. At the top of its path its instantaneous speed is A. 50 m/s B. 20 m/s C. 10 m/s D. -10 m/s E. 0 M/s

E

A speeding truck slams its brakes and it skids to a stop. If the truck's total mass were doubles, the skidding distance would be A. Half as far B. Nearly as far, but not quite C. Twice as far D. Four times as far E. The same

E

After a cannon ball is fired into frictionless space, the amount of force needed to keep it going equals: A. Twice the force with which it was fired B. The same amount of force with which it was fired C. One half of the force with which it was fired D. One quarter of the force with which it fired E. Zero since no force is necessary to keep it moving in space

E

Potential energy is the energy an object has because of its: A. Speed B. Density C. Size D. Temperature E. Location

E

Suppose you take a trip that covers 240 km and takes 4 hours. Your average speed is A. 960 km/hr B. 480 km/hr C. 240 km/hr D. 120 km/hr E. 60 km/hr

E

The force of an apple hitting the ground depends upon A. Air resistance on the apple as it falls B. The speed of the apple just before it hits the ground C. The time of impact with the ground D. Whether or not the apple bounces E. All of the above

E