Physics Test Ch 1-6

A ball tossed vertically upward rises, reaches its highest point, and then falls back to its starting point. During this time the acceleration of the ball is always opposite its velocity. directed upward. directed downward. in the direction of motion.

directed downward

The difference between speed and velocity involves _______. direction the magnitude of each acceleration path length

direction

The two measurements necessary for calculating average speed are distance and acceleration. velocity and time. velocity and distance. distance and time. acceleration and time.

distance and time

What is the net force on a crate sliding at an unchanging speed when pushed with a steady force of 75 N? 75 N Somewhat less than 75 N Slightly more than 75 N Zero

0

Consider a pair of forces, one having a magnitude of 20 N and the other a magnitude of 12 N. What maximum net force is possible for these two forces? What is the minimum net force possible?

32N ; 8N

At one instant a heavy object in air is moving upward at 50 meters per second. One second later its speed is approximately 50 m/s. 55 m/s. 60 m/s. 40 m/s.

40 m/s

A 400 kg bear grasping a vertical tree slides down at constant velocity. What is the friction force that acts on the bear?

4000 N

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 800 N. 200 N. 400 N. none of these

400N

In its first second of free fall, a dropped softball will fall a vertical distance of _______. 5 m 15 m 10 m 20 m

5 m

You toss a ball straight up with an initial speed of 34 m/s. How high does it go? How long is it in the air (neglecting air resistance)?

58 m 6.8 s

If a car increases its velocity from zero to 60 km/h in 10 seconds, its acceleration is 10 km/h/s. 60 km/h/s. 3 km/h/s. 600 km/h/s. 6 km/h/s.

6 km/h/s

Lucy Lightfoot stands with one foot on one bathroom scale and her other foot on a second bathroom scale. Each scale reads 320 N. What is Lucy's weight?

640N

Two 5-N vectors at an angle of 90° to each other have a resultant force of about _______. 5 N 7 N 0 N 10 N

7 N

What is the instantaneous velocity of a freely falling object 7.0 s after it is released from a position of rest? What is its average velocity during this 7.0-s interval? How far will it fall during this time?

70 m/s 35 m/s 250 m

If the strong man exerts a downward force of 800 N on the rope, how much upward force is exerted on the block?

800N

It takes 6 seconds for a stone to fall to the bottom of a mine shaft. How deep is the shaft? about 180 m more than 200 m about 60 m about 120 m

about 180 m

What did Copernicus say about the motion of the Sun? The Sun circles the Earth each 365 days. The Sun is stationary and the Earth circles it. The Sun circles the Earth each 24 hours. The Sun rises and falls each 24 hours.

The Sun is stationary and the Earth circles it

A Volkswagen bug and a Volvo truck have a head-on collision. Which statement is true? Both forces are identical. The magnitudes of both forces are the same. The greater force acts on the Volkswagen bug. The greater force acts on the Volvo truck

The magnitudes of both forces are the same

Which of the following is a scientific statement? There are things we will never know about. Matter is filled with undetectable particles. There are parts of the universe that will never be found by man. The moon is made of green cheese. none of these

The moon is made of green cheese

If a block is moving to the left at a constant velocity, what can one conclude? There is exactly one force applied to the block. The net force applied to the block is directed to the left. The net force applied to the block is zero. There must be no forces at all applied to the block.

The net force applied to the block is zero

Does a falling object increase in speed if its acceleration of fall decreases? No. Yes.

Yes

A theory in science is _______. forever true an educated guess a synthesis of well-tested ideas an agreement between trained investigators

a synthesis of well tested ideas

Surprisingly, very few athletes can jump more than 2 feet (0.6 m) straight up. Use d=1/2gt2 and solve for the time one spends moving upward in a 0.6-m vertical jump. Then double it for the "hang time"-the time one's feet are off the ground. Express your answer to two significant figures and include the appropriate units.

0.70 s

Consider a mass of 1 kg accelerated 1 m/s2 by a force of 1 N. Find the acceleration for a force of 2 N acting on 2 kg.

1 m/s2

If a projectile is fired straight up at a speed of 10 m/s, the time it takes to reach the top of its path is about 2 seconds. 10 seconds. 1 second. not enough information to estimate

1 second

An apple falls from a tree and hits the ground 5 meters below. It hits the ground with a speed of about 5 m/s. 20 m/s. 15 m/s. 10 m/s. not enough information given to estimate

10 m/s

A car accelerates at 2 meters/s/s. Assuming the car starts from rest, how far will it travel in 10 s? 40 m 2 m 10 m 100 m 200 m

100 m

A baseball player bats a ball with a force of 1000 N. The reaction force that the ball exerts against the bat is 1000 N. more than 1000 N. less than 1000 N. impossible to determine.

1000 N

The force of friction on a sliding object is 10 N. The applied force needed to maintain a constant velocity is more than 10 N. 10 N. less than 10 N.

10N

What is the net force when a pair of 5-N forces simultaneously act in the same direction on an object? 10 N 5 N 7.5 N 0 N

10N

The distance between the Earth and the Sun is approximately _______. twice the distance between the Earth and the Moon 110 Moon diameters 110 Sun diameters 150,000 m

110 Sun diameters

While you're in a bus that moves at 100 km/h, you walk from the back to the front at 10 km/h. What is your speed relative to the road outside? 110 km/h 90 km/h 100 km/h 10 km/h

110 km/h

If a projectile is fired straight up at a speed of 10 m/s, the total time to return to its starting position is about 10 seconds. 20 seconds. 1 second. 2 seconds. not enough information to estimate

2 seconds

A horse gallops a distance of 10 kilometers in a time of 30 minutes. Its average speed is 15 km/h. 20 km/h. 30 km/h. 40 km/h.

20 km/h

If you pull horizontally on a crate with a force of 200 N, it slides across the floor in dynamic equilibrium. How much friction is acting on the crate?

200 N

How much support force acts on a 200-N girl standing on a weighing scale? 200 N No support force unless she stands on the floor Less than 200 N More than 200 N

200N

An object falls freely from rest on a planet where the acceleration due to gravity is twice as much as it is on Earth. In the first 5 seconds it falls a distance of 100 m. 150 m. 250 m. 500 m. none of these

250 m

A ball freely falling at 20 m/s will in the next second have a speed of _______. 10 m/s 30 m/s 20 m/s more than 30 m/s

30 m/s

A grocery bag can withstand 300 N of force before it rips apart. How many kilograms of apples can it safely hold? Express your answer with the appropriate units.

30.6 kg

Newton said that something was needed to change the motion of an object. A clear reading of his first law tells us that what is needed is _______. a non-zero net force a net force no force at all a force

A non-zero net force

Which best describes what occurs when a body accelerates? Change in velocity per unit time Change in direction Change Change in velocity

Change in velocity per unit time

Which of the following are scientific hypotheses? Chlorophyll makes grass green. Earth rotates about its axis because living things need an alternation of light and darkness. Tides are caused by the Moon.

Chlorophyll makes grass green and Tides are caused by the moon

The Greek mathematician Eratosthenes made measurements to show the size of _______. Earth the Sun the Moon all of the given answers

Earth

The scientist to first introduce the concept of inertia was Aristotle. Copernicus. Newton. Galileo.

Galileo

What did Galileo demonstrate in his Leaning Tower of Pisa experiment? He demonstrated that light and heavy objects gain the same amount of speed when falling. He demonstrated that the forces on falling objects are the same. He demonstrated that heavy objects fall faster than light objects. He demonstrated that air resistance has no effect on falling objects.

He demonstrated that light and heavy objects gain the same amount of speed when falling.

What was the greatest discovery by Galileo during his inclined-plane experiments? He discovered that light and heavy objects gain the same speed when rolling on inclines. He discovered that heavy objects roll faster than light objects on an incline. He discovered that balls rolling down an incline gain speed, and balls rolling up an incline lose speed. He discovered that a ball rolling down an incline and onto a horizontal surface would roll indefinitely.

He discovered that a ball rolling down an incline and onto a horizontal surface would roll indefinitely.

A speedometer normally measures _______. instantaneous speed average speed distance traveled velocity

Instantaneous speed

A block of mass 2kg is acted upon by two forces: 3N (directed to the left) and 4N (directed to the right). What can you say about the block's motion? It must be moving to the left. It must be moving to the right. It must be at rest. It could be moving to the left, moving to the right, or be instantaneously at rest.

It could be moving to the left, moving to the right, or be instantaneously at rest.

A ball rolling along a floor doesn't continue rolling indefinitely. Is it because it is seeking a place of rest or because some force is acting upon it? It is because it is seeking a place of rest. It is because some force is acting upon it.

It is because some force is acting upon it

What two classes of motion did Aristotle advocate? Earthly motion and heavenly motion Natural motion and violent motion Vertical motion and horizontal motion Propelled motion and passive motion

Natural motion and violent motion

Which of Newton's laws does the equilibrium rule illustrate? Newton's law of gravity Newton's third law Newton's first law Newton's second law

Newtons first law

Since an object weighs less on the surface of the Moon than on Earth's surface, does it have less inertia on the Moon's surface? Yes. No.

No

A force of gravity pulls downward on a book on a table. What force prevents the book from accelerating downward?

Normal force

Which of these is the most basic science? Physics Chemistry Biology Astronomy

Physics

A package falls off a truck that is moving at 30 m/s. Neglecting air resistance, the horizontal speed of the package just before it hits the ground is less than 30 m/s but larger than zero. about 30 m/s. more than 30 m/s. zero. More information is needed for an estimate.

about 30 m/s

Disregarding air resistance, objects fall with constant acceleration. velocity. speed. distances each successive second.

acceleration

Galileo discovered that when air resistance can be neglected, all objects fall with the same _______. distance acceleration energy of motion speed

acceleration

When we're talking about how quickly "how fast" changes, we're talking about _______. acceleration the difference between speed and velocity free-fall physics increases in falling distance

acceleration

Hang from a pair of gym rings and the upward support forces of the rings will always each be half your weight. add up to equal your weight. each equal your weight.

add up to equal your weight

When you stand at rest on a pair of bathroom scales, the readings on the scales will always add up to equal your weight. each equal your weight. each be half your weight.

add up to equal your weight

A truly educated person is knowledgeable about science. religion. the arts. all of these

all of these

An object in mechanical equilibrium is an object moving with constant velocity. at rest. having no acceleration. all of these

all of these

Compared to a 1-kg block of solid iron, a 2-kg block of solid iron has twice as much volume. inertia. mass. all of these none of these

all of these

Which of the following involves passion, talent, and intelligence? art literature science music all of these

all of these

A fact in science is _______. an educated guess a synthesis of well-tested ideas an agreement between trained investigators forever true

an agreement between trained investigators

Which has the greater mass? an automobile battery a king-size pillow neither - both have the same

an automobile battery

An archer shoots an arrow. Consider the action force to be the bowstring against the arrow. The reaction to this force is the arrow's push against the bowstring. combined weight of the arrow and bowstring. grip of the archer's hand on the bow. friction of the ground against the archer's feet. air resistance against the bow.

arrow's push against the bowstring

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 Arnold, of course. Suzie, surprisingly. both the same, interestingly enough.

both the same, interestingly enough

Two forces, of magnitude 4N and 10N, are applied to an object. The relative direction of the forces is unknown. The net force acting on the object __________. cannot have a magnitude equal to 5N cannot have a magnitude equal to 10N cannot have the same direction as the force with magnitude 10N must have a magnitude greater than 10N

cannot have a magnitude equal to 5N

If an object moves with constant acceleration, its velocity must change by varying amounts depending on its speed. always decrease. change by the same amount each second. be constant also.

change by the same amount each second

Eratosthenes learned about the position of the sun on June 22 by setting up sticks at both Syene and Alexandria. setting up a stick at Alexandria. setting up a stick at Syene. consulting library information. None of the above choices are correct.

consulting library information

A skydiver jumps from a high-flying plane. As her velocity of fall increases, her acceleration decreases. increases. remains unchanged regardless of air resistance.

decreases

A truck is moving at constant velocity. Inside the storage compartment, a rock is dropped from the midpoint of the ceiling and strikes the floor below. The rock hits the floor behind the midpoint of the ceiling. exactly below the midpoint of the ceiling. ahead of the midpoint of the ceiling. More information is needed to solve this problem. none of these

exactly below the midpoint of the ceiling

Whereas Aristotle relied on logic in explaining nature, Galileo relied on experiment. patterns. logic also. mathematics.

experiment

Whirl a rock at the end of a string and it follows a circular path. If the string breaks, the tendency of the rock is to increase its speed. revolve in a smaller circle. continue to follow a circular path. follow a straight-line path.

follow a straight line path

The newton is a unit of mass. force. inertia. density.

force

When a scientist is dishonest and reports false information, he or she gets no second chance in the scientific community. like in so many other professions, will be excused by the scientific community.

gets no second chance in the scientific community

In science, an educated guess is a theory. hypothesis. both of these

hypothesis

If, while riding in a smooth-riding train, you toss a coin upward, the coin will normally land _______. in front of you in back of you in your hand off to the side of you

in your hand

In each second of fall, the distance a freely falling object will fall is about 5 m. about 10 m. increasing. the same, but not 5 m or 10 m. none of these

increasing

If one object has twice as much mass as another object, it also has twice as much velocity. acceleration due to gravity. volume. inertia. all of these

inertia

A kilogram is a measure of an object's mass. force. weight. size

mass

A massive block is being pulled along a horizontal frictionless surface by a constant horizontal force. The block must be __________. continuously changing direction moving at constant velocity moving with a constant nonzero acceleration moving with continuously increasing acceleration

moving with a constant nonzero acceleration

The direction of the force of friction on a sliding crate is _______. nondirectional in the same direction as the force that produces sliding opposite to the direction of sliding usually at right angles to the force that produces sliding

opposite to the direction of sliding

The team that will win in a tug-of-war is the team that _______. pushes harder on the floor while holding the rope has the greater self confidence. pulls with the greater force yanks the rope

pushes harder on the floor while holding the rope

When hitting a tennis ball with your racquet, the force on the ball has the same magnitude as the force on the _______. racquet, and in the same direction racquet hand that holds the racquet player

racquet

The force that propels a rocket is the force provided by _______. ejected fuel decreased mass the expelled gas pushing on the rocket energetic reactions as the fuel is burned

the expelled gas pushing on the rocket

Your weight is the gravitational attraction force between you and the Earth. equal to your mass. a property of mechanical equilibrium. all of these

the gravitational attraction force between you and the Earth

A sheet of paper can be withdrawn from under a container of milk without toppling it if the paper is jerked quickly. This best demonstrates that the milk carton has no acceleration. there is an action-reaction pair of forces. gravity tends to hold the milk carton secure. the milk carton has inertia. none of these

the milk carton has inertia

An object cannot remain at rest unless which of the following holds? The net force acting on it is zero. The net force acting on it is constant and nonzero. There are no forces at all acting on it. There is only one force acting on it.

the net force acting on it is zero

The unit of mass is the kilogram, and the unit of weight is _______. metric mass the kilogram also the newton m/s2

the newton

A rock weighs 30 N on Earth. A second rock weighs 30 N on the moon. Which of the two rocks has the greater mass? the one on Earth the one on the moon They have the same mass. not enough information to say

the one on the moon

Compared to the mass of a certain object on Earth, the mass of the same object on the moon is six times as much. the same. zero. one sixth as much.

the same

Each second, a ball rolling down an inclined plane picks up _______. increasing amounts of speed decreasing amounts of speed the same amount of speed acceleration, not speed

the same amount of speed

A boxer cannot exert much force on a piece of tissue paper suspended in air because _______. the time of the interaction is too brief the tissue paper has too little mass to exert much force on the boxer's fist there is little follow-through with the punch the tissue lacks enough strength

the tissue paper has too little mass to exert much force on the boxer's fist

While an object near the Earth's surface is in free fall, its acceleration increases. mass increases. velocity increases. mass decreases.

velocity increases

A crate sits at rest on a factory floor. Friction between the crate and floor occurs _______. even when no pushing occurs only if the crate is pushed vertically as well as horizontally when the crate is pushed horizontally, whether it slides or not only if the crate is sliding

when the crate is pushed horizontally, whether it slides or not

A scientific hypothesis deemed valid must have a test for proving it _______. correct wrong more than one time None of these choices is correct

wrong

A car maintains a constant velocity of 100 km/hr for 10 seconds. During this interval its acceleration is 10 km/hr. 1000 km/hr. zero. 110 km/hr.

zero

A hockey puck is set in motion across a frozen pond. If ice friction and air resistance are neglected, the force required to keep the puck sliding at constant velocity is equal to the product of its mass times its weight. zero. equal to its weight. equal to its weight divided by its mass.

zero