Physical Science Unit 1-4

A glass rod which is electrically neutral has which of the following? more protons than electrons no protons or electrons equal numbers of protons and electrons only neutrons, but no protons or electrons more electrons than protons

equal numbers of protons and electrons

The man jumps out of an airplane, falls for a while, and then opens his parachute. After a short time, he is falling with constant speed straight down. What forces are acting on the man? 1 force up 2 forces which do not balance no forces 1 force down 2 forces which balance

2 forces which balance

A ball is thrown upward. When the ball is at its maximum height, what is its acceleration? It is impossible to tell from the information given. 9.8 m/sec2 upward 0 (It is not accelerating.) 9.8 m/sec2 downward

9.8 m/sec2 downward

Select all correct answers. The four fundamental interactions are contact force. gravitational force. frictional force. weak nuclear force. electromagnetic force. strong nuclear force. centrifugal force.

gravitational force. weak nuclear force. electromagnetic force. strong nuclear force.time symmetry

A rock is sitting on top of a hill. What type of energy does the rock have by virtue of its position? nuclear potential energy electric potential energy gravitational potential energy kinetic energy thermal energy

gravitational potential energy

Referring to this picture, where is the pressure greater? at A at B neither, the pressures are the same

neither, the pressures are the same

A clock that is moving close to the speed of light runs _________ than when the clock is stationary. slower at the same speed faster

slower

According to Archimedes' Principle, upon what does the buoyant force depend? the amount of displaced fluid the weight of the submerged object the total volume of the fluid the density of the submerged object

the amount of displaced fluid

The next two questions deal with a pendulum swinging back and forth without any friction in the system, as pictured here: Which of the following quantities is conserved? potential energy of the pendulum angular momentum of the pendulum linear momentum of the pendulum total energy of the pendulum all of the above

total energy of the pendulum

Changing electric fields create magnetic fields. true false

true

A raindrop, as it falls to the ground, reaches a speed known as terminal velocity where the speed of the raindrop is neither increasing nor decreasing. This motion of the raindrop at terminal velocity can be understood in terms of: one vertical force one horizontal force two vertical forces which balance two vertical forces which do not balance two horizontal forces which balance two horizontal forces which do not balance

two vertical forces which balance

When paper burns, what happens to its mass? All of the mass is still there, but some of the atoms have recombined into different molecules and dissipated through the air. A measureable amount of the mass is destroyed in the burning. The mass increases as a result of the burning.

All of the mass is still there, but some of the atoms have recombined into different molecules and dissipated through the air.

When the dynamite explodes, what happens to its mass? A measurable amount of the mass is destroyed in the explosion. The mass increases as a result of the explosion. All of the mass is still there, but some of the atoms have recombined into different molecules and dissipated through the air.

All of the mass is still there, but some of the atoms have recombined into different molecules and dissipated through the air.

In the picture, a boy is stopped at the top of a gentle hill. He starts down the hill, sleds at a constant speed for a short time, then slows down and stops at the bottom. The following questions ask you to describe what is happening at various points along his path. At which of the points would the net force on the sled be zero? At none of these points; the force can't be zero while the sled is moving. At point 2. At point 3. At point 4. At points 2-4.

At point 3.

In the picture, a boy is stopped at the top of a gentle hill. He starts down the hill, sleds at a constant speed for a short time, then slows down and stops at the bottom. The following questions ask you to describe what is happening at various points along his path. When would the boy's acceleration be directed backwards (opposite the direction he is moving)? At none of the points. His acceleration is forward as long as he is moving forwards. At point 2. At point 3. At point 4. At point 1. At point 5.

At point 4.

According to the course material, what is the suggested procedure to analyze forces on an object? Choose an object; Is gravity important? Is the object charged? What are the 3rd law reaction forces on the nearby objects? Choose an object; Is gravity important? How fast is the object moving? What are the 3rd law reaction forces on the nearby objects? Identify all the gravitational, electrical, and contact forces on all of the objects discussed in the problem. Choose an object; is gravity important? Is the object charged, carrying current, or magnetic? What does the object touch? Is friction important?

Choose an object; is gravity important? Is the object charged, carrying current, or magnetic? What does the object touch? Is friction important?

When a spinning figure skater pulls her arms in, she spins faster. Which of the following laws best explains why she speeds up in this situation? Newton's 1st law Newton's 2nd law Newton's 3rd law Conservation of Angular Momentum Conservation of Energy

Conservation of Angular Momentum

When a glass rod is rubbed with a piece of vinyl, the glass becomes positively charged. Why does this happen? Electrons in the glass are annihilated by the protons in the vinyl. Protons are transferred from the glass to the vinyl. Protons are transferred from the vinyl to the glass. Electrons are transferred from the glass to the vinyl. Electrons are transferred from the vinyl to the glass.

Electrons are transferred from the glass to the vinyl.

When you rub a balloon in your hair, the balloon becomes negatively charged. What is the correct explanation for this charge? Electrons in the hair annihilate protons in the balloon. The balloon is a conductor. Electrons are transferred from the hair to the balloon. Protons are transferred from the balloon to the hair. Friction creates negative charges.

Electrons are transferred from the hair to the balloon.

A driver in a Volkswagen bug (mass = 1335 kg) pulls out going 10 miles per hour in front of a Ford pickup truck (mass = 2675 kg), which is traveling 40 miles per hour. The two vehicles experience a head-on collision. A passenger in the Volkswagen is not wearing a seat belt. He is thrown toward the windshield. Which of the following is a correct explanation for this occurrence? The car is still exerting a forward force on him for a short time after the accident, and this force propels him forward. He is not thrown forward. He just keeps moving in the direction he was originally going until something, like the windshield, stops him. The impact exerts a forward force on the occupants of the car. The force of impact is backward, so there is an opposite and equal force forward on the occupants.

He is not thrown forward. He just keeps moving in the direction he was originally going until something, like the windshield, stops him.

Which of the following describes thermal energy? It depends on the density and buoyant force. It depends on temperature. It depends on the distance between charged particles. It depends on the mass and height. It depends on the mass and speed.

It depends on temperature.

Which of the following describes Newton's 2nd law? It states that an object will remain in uniform motion unless acted upon by a force. Like charges repel, opposite charges attract. It states that objects eventually stop unless a force is applied. It describes how an object accelerates when a force is applied. It states that forces come in interaction pairs. It states that objects with mass attract each other.

It describes how an object accelerates when a force is applied.

What is true about the pressure in a fluid? It increases with the volume of the container. It depends on the shape of the container. It increases with depth. It increases with area it is pushing on. It is zero.

It increases with depth.

Imagine this scenario: A small fishing boat is floating by a dock at the lake. A person gets into a boat. As the boat sinks deeper into the water, what happens to the pressure on the bottom surface of the boat? It increases. It decreases. It remains the same.

It increases.

What happens to the pressure on the block as it is pushed deeper into the water? It increases. It decreases. It stays the same. It changes from upward to zero It changes from upward to downward

It increases.

A cue ball is fired at a group of pool balls on a frictionless pool table. Compare the total momentum before and after the cue ball hits the other balls. It was smaller before the collision. It is the same before and after the collision. It was larger before the collision.

It is the same before and after the collision.

Which of the following describes Newton's 1st law? It describes how an object accelerates when a force is applied. It states that an object will remain in uniform motion unless acted upon by a force. It states that objects eventually stop unless a force is applied. It states that forces come in interaction pairs. It states that objects with mass attract each other. Like charges repel, opposite charges attract.

It states that an object will remain in uniform motion unless acted upon by a force.

Which of the following describes Newton's 3rd law? It states that forces come in interaction pairs. It describes how an object accelerates when a force is applied. Like charges repel, opposite charges attract. It states that an object will remain in uniform motion unless acted upon by a force. It states that objects eventually stop unless a force is applied. It states that objects with mass attract each other.

It states that forces come in interaction pairs.

What happens as a body moves higher and higher above the surface of the Earth? Its weight increases. Its weight decreases. Its mass increases. Its mass decreases. Both its weight and its mass decrease.

Its weight decreases.

Two objects are attracted to each other by electromagnetic forces. Suppose I double the charge of one object. How can I return the force to its original value? Double the charge of the second object. Move the objects farther apart. Move the objects closer together. Do nothing. The force doesn't change unless the charge of both objects changes. None of these returns the force to its original value.

Move the objects farther apart.

Which of the following statements is true? Moving clocks run fast. Non-inertial reference frames do not exist. Two events that are simultaneous on one reference frame are always simultaneous in another reference frame. Moving objects are shorter than when they are at rest.

Moving objects are shorter than when they are at rest.

Which of the following statements is true concerning their motion? The ant will stop first due to its smaller mass. The elephant and ant will stop at the same time. The elephant will stop first due to its larger mass. Neither the elephant nor the ant will stop. Both will continue at 1 mile per hour as long as the ice lasts.

Neither the elephant nor the ant will stop. Both will continue at 1 mile per hour as long as the ice lasts.

According to principle of non-contradiction, if two ideas contradict each other, which of the following statements is true? The simplest statement must be true. Both statements must be false. One statement must be false. One statement must be false and the other statement must be true. Both statements must be true.

One statement must be false.

A driver in a Volkswagen bug (mass = 1335 kg) pulls out going 10 miles per hour in front of a Ford pickup truck (mass = 2675 kg), which is traveling 40 miles per hour. The two vehicles experience a head-on collision. Which of the following statements is true concerning the forces that each vehicle (and driver) experience in this collision? The Volkswagen bug experiences a much smaller force than the Ford pickup truck due to the smaller speed of the Volkswagen bug. The Volkswagen bug experiences a much smaller force than the Ford pickup truck due to the smaller mass of the Volkswagen bug. The Volkswagen bug experiences a much greater force than the Ford pickup truck due to the greater speed of the truck. The Volkswagen bug experiences a force that is the same as the Ford pickup truck experiences. The Volkswagen bug experiences a much greater force than the Ford pickup truck due to the larger mass of the truck.

The Volkswagen bug experiences a force that is the same as the Ford pickup truck experiences.

A bullet is fired horizontally from a high-powered rifle. At the same time, a second bullet is simply dropped from the same height as the bullet which was fired from the rifle. Neglecting air resistance, which statement is true about the acceleration of the first bullet after it leaves the gun compared to that of the second bullet as it falls? The acceleration of the first bullet is much less than the acceleration of the bullet that was dropped. The acceleration of the first bullet is a little less than the acceleration of the bullet that was dropped. The acceleration of the first bullet is the same as the acceleration of the bullet that was dropped. The acceleration of the first bullet is a little more than the acceleration of the bullet that was dropped. The acceleration of the first bullet is much more than the acceleration of the bullet that was dropped.

The acceleration of the first bullet is the same as the acceleration of the bullet that was dropped.

An object is initially moving under the influence of gravity. How does air friction change the acceleration of this object as the object increases in speed? The acceleration of the object increases as its speed increases. The acceleration of the object decreases as its speed increases. All objects accelerate the same amount regardless of speed.

The acceleration of the object decreases as its speed increases.

A driver in a Volkswagen bug (mass = 1335 kg) pulls out going 10 miles per hour in front of a Ford pickup truck (mass = 2675 kg), which is traveling 40 miles per hour. The two vehicles experience a head-on collision. In this same head-on collision between the Volkswagen bug and the Ford pickup truck, which of the following statements is true concerning the acceleration of the pickup truck and Volkswagen bug? The truck experiences no acceleration but the Volkswagen bug experiences a large acceleration. The acceleration of the truck is much less than that of the Volkswagen bug. The acceleration of the truck is much greater than that of the Volkswagen bug. The acceleration of the truck is the same as that of the Volkswagen bug.

The acceleration of the truck is much less than that of the Volkswagen bug.

Two helpful Physical Science 100 students happen to see the plight of the elephant and the ant on the ice and decide to help them. The two students exert a force on the elephant of 1 N and a force on the ant of 1 N. Which of the following statements is true? The ant will stop first due to its smaller mass. Neither the elephant nor the ant will stop. Both will continue at 1 mile per hour as long as the ice lasts. The elephant will stop first due to its larger mass. The elephant and ant will stop at the same time.

The ant will stop first due to its smaller mass.

For the next two questions, two charged balls are placed next to each other as shown by the diagrams in the question. The charge of the balls and the distance between the balls is accurately represented. The large ball has a mass of 2 kilograms; all other balls are 1 kilogram. In which picture will the electrical force between the two balls be the largest?

The ball with the +1 and the +2 closest together

Now this same block of wood that was floating with one half of its volume out of the water is pushed down so that it is completely underneath the water. Which of the following statements is correct? The buoyant force on the block is the same in the two cases because the weight per unit volume of the wood has not changed. The buoyant force on the block is the same in the two cases because the weight per unit volume of the water is the same in each case. The buoyant force on the block is greater when the block is completely submerged than it is when the block is floating. The buoyant force on the block is greater when it is floating than when it is totally submerged. The buoyant force on the block is the same in the two cases because the block loses weight as it is submerged.

The buoyant force on the block is greater when the block is completely submerged than it is when the block is floating.

A small, steel ball sinks in water while a very large aircraft carrier, made of the same kind of steel, floats at rest on the surface of the water. Which of the following is correct? The buoyant force on the carrier is greater than the weight of the carrier. The weight of the ball is greater than the weight of the carrier. The buoyant force on the carrier is the same strength as the weight of the carrier. The buoyant force on the ball acts downward while that on the carrier acts upward. The buoyant force on the ball is greater than the buoyant force on the carrier.

The buoyant force on the carrier is the same strength as the weight of the carrier.

relate to a cannon ball and a marble that are dropped from the same height at the same time. Both are originally at rest. Ignore air friction. Which is easier to accelerate? The cannonball requires more force to accelerate it as much as the marble. The cannonball requires less force to accelerate it as much as the marble. The cannonball and the marble will accelerate the same amount in response to the same force.

The cannonball requires more force to accelerate it as much as the marble.

Which one of the following is classified as an electrical force? The force holding the sun and planets together in a solar system. The force holding stars together in a galaxy. The force attracting the electrons to the nucleus in an atom. The force that causes a ball that is thrown upward to return to the earth. The force holding protons and neutrons together in a nucleus.

The force attracting the electrons to the nucleus in an atom.

Which of the following best describes the strong interaction? The force between two charged particles The force between two accelerating objects A force between objects with mass The force between action reaction pair The force that holds the nucleus of an atom together

The force that holds the nucleus of an atom together

If a quantity is conserved, what happens? The amount of that quantity can change but not the form. The form of the quantity can change but not the amount. Both the amount and form of that quantity can change. The amount and form of that quantity do not change.

The form of the quantity can change but not the amount.

A train moving near the speed of light enters a tunnel. According to a person standing in the middle of the tunnel, the back end of the train enters the tunnel just as the front end is emerging. What happens according to someone sitting in the middle of the train? The back end enters the tunnel at the same time as the front end emerges. The front and back ends of the train enter the tunnel at the same time. The back end enters the tunnel before the front end emerges. The front end leaves the tunnel before the back end enters. The front end leaves the tunnel at the same time the back end passes the person standing in the middle of the tunnel.

The front end leaves the tunnel before the back end enters.

relate to a cannon ball and a marble that are dropped from the same height at the same time. Both are originally at rest. Ignore air friction. How does the gravitational force on the cannonball compare with that on the marble? The gravitational force on the cannonball is larger. The gravitational force on the cannonball is smaller. The gravitational force on the cannon ball is the same as the force on the marble.

The gravitational force on the cannonball is larger.

Where is the kinetic energy of the pendulum the largest? The kinetic energy is highest at the highest point in the swing (point A). The kinetic energy is highest in the middle of the swing (point B). The kinetic energy is highest at the lowest point in the swing (point C). The pendulum has no kinetic energy. The pendulum has constant kinetic energy throughout its motion.

The kinetic energy is highest at the lowest point in the swing (point C).

A stick of dynamite explodes. How does the momentum of the dynamite before the explosion compare to the total momentum of all of the pieces immediately after the explosion? The momentum is the same just before and just after the dynamite explodes. The momentum is larger after the explosion. The momentum is larger before the explosion.

The momentum is the same just before and just after the dynamite explodes.

All objects weigh less near the surface of the Moon than the same objects weigh near the surface of the Earth. Why does this happen? The buoyant force on the Moon is greater than on earth. The universal gravitational constant is smaller near the Moon. The moon has a smaller radius than the Earth. There is less air on the Moon's surface. The moon has less mass than the Earth.

The moon has less mass than the Earth.

If an object has kinetic energy, what must be true? The object is at rest. The object is at an elevated position. The object is electrically charged. The object has some potential energy stored in chemical bonds. The object is moving.

The object is moving.

Look at this diagram of 4 containers to answer the question: Note: The containers are numbered 1-4 from the left to the right. The pressure is measured at the bottom of each container. If you put them in order of increasing pressure (smallest first, largest last) what is the correct order? The pressures are all the same. 4, 3, 2, 1 1, 2, 3, 4 4 is smallest, but the others are the same. You cannot tell without knowing the volumes of the containers.

The pressures are all the same.

For the next two questions, two charged balls are placed next to each other as shown by the diagrams in the question. The charge of the balls and the distance between the balls is accurately represented. The large ball has a mass of 2 kilograms; all other balls are 1 kilogram. When the two spheres in diagram a are brought nearer to each other, what happens to the electric force between them? The attractive force gets larger. The size of the force gets smaller. The force reverses direction. The repulsive force gets larger. The force remains the same.

The repulsive force gets larger.

A heavy rock is lying under water on the bottom of a swimming pool. Which of the following is correct? The rock is harder to lift when it is under water than it would be on dry land because the water pressure pushing down on it helps hold it down. The rock is easier to lift when it is under water than it would be on dry land because the buoyant force of the water pushing on the rock helps to push it upward. It requires no more force to lift a rock under water than it does on dry land, and also it requires no less force—the situation is the same in either case. The rock is significantly easier to lift when it is under water because its actual weight is less in water—the earth pulls on it differently. The rock is significantly harder to lift when it is under water because the buoyant force acts in addition to its weight, making a greater force necessary.

The rock is easier to lift when it is under water than it would be on dry land because the buoyant force of the water pushing on the rock helps to push it upward.

A rocket in empty space is a long distance from any star or planet so that we ignore any influence from these bodies. When the motors are turned off, which of the following is true? The rocket will stop eventually as it uses up its store of motion. The rocket will continue to increase its speed for a little while and then will finally coast to a stop. The rocket will continue with unchanging speed in a straight line. The rocket will stop dead immediately. The rocket will slowly decrease its speed, but will never come to a complete halt.

The rocket will continue with unchanging speed in a straight line.

In the picture, a boy is stopped at the top of a gentle hill. He starts down the hill, sleds at a constant speed for a short time, then slows down and stops at the bottom. The following questions ask you to describe what is happening at various points along his path. Which of the following best explains what happens at the bottom of the hill? The sled instantly comes to rest because there are no more forces acting on it, and therefore it stops immediately. The sled slowly comes to rest because there are no more forces acting on it, and therefore its momentum runs out and it stops gradually. The sled slowly comes to rest because of gravitational forces. The sled slowly comes to rest because of a net force acting backwards. The sled instantly comes to rest because all the forces acting on it are now balanced, so there is nothing to keep it moving.

The sled slowly comes to rest because of a net force acting backwards.

relate to a cannon ball and a marble that are dropped from the same height at the same time. Both are originally at rest. Ignore air friction. How do the speed and acceleration of the cannonball compare with those of the marble at any given time after they are dropped? The speed of the cannonball is the same, but the acceleration is larger. The speed and acceleration of the cannonball are both greater than those of the marble. The speed and acceleration of the cannonball are both the same as those of the marble. The speed and acceleration of the cannonball are both smaller than those of the marble. The acceleration of the cannonball is the same, but the speed is larger.

The speed and acceleration of the cannonball are both the same as those of the marble.

In the picture, a boy is stopped at the top of a gentle hill. He starts down the hill, sleds at a constant speed for a short time, then slows down and stops at the bottom. The following questions ask you to describe what is happening at various points along his path. The boy and the sled exert forces on each other. When would the contact force the sled exerts on the boy be equal to the contact force the boy exerts on the sled? The two forces are always equal and opposite. Only at 2. Only at 3. Only at 4. Only at 5.

The two forces are always equal and opposite.

In convection currents, warmer air rises and cooler air descends. Which of the following is correct? There is a buoyant force on the warmer air, but there is not a buoyant force on the cooler air. The gravitational force pulls harder on each kilogram of cooler air than it does on a kilogram of warmer air. The buoyant force on the warmer air is upward, while the buoyant force on the cooler air is downward. The warmer air has a lower density than the cooler air which it displaces. The warmer air has a higher density than the cooler air which it displaces.

The warmer air has a lower density than the cooler air which it displaces.

If a block of wood floats with half its volume submerged, what happens? The buoyant force is equal to half the weight of the block. The weight of the block is the same as that of the displaced water. The volume of the block is the same as that of the displaced water. The buoyant force is equal to twice the weight of the displaced water. The buoyant force is equal to twice the weight of the block.

The weight of the block is the same as that of the displaced water.

You are in a spaceship moving in a straight line at constant speed. You cannot see out of the ship. Assuming perfectly uniform motion, which of the following is true? You could determine that you are moving by measuring changes in the motion of a ball thrown perpendicular to the direction you are traveling. You could determine that you are moving by measuring changes in the motion of a ball thrown parallel to the direction you are traveling. You could determine that you are moving by measuring changes in the motion of a ball thrown perpendicular to the direction you are traveling or by measuring the change in length of the ship you are in. There is no experiment you can do to determine that you are moving. You could determine that you are moving by measuring the change in length of the ship you are in.

There is no experiment you can do to determine that you are moving.

The Sun has a mass about 330,000 times as large as the Earth. Why aren't we more strongly attracted to the Sun than the Earth? The Sun's gravity is weakened by the other planets in the solar system. The intense heat of the Sun weakens its gravitational field. The moon disrupts the Sun's gravitational pull. We are much closer to the Earth than we are to the Sun.

We are much closer to the Earth than we are to the Sun.

When is a frame of reference inertial? When the reference frame has constant velocity. When the reference frame has constant acceleration. When the reference frame is moving the same way as the objects that are in the reference frame. When the reference frame has constant speed.

When the reference frame has constant velocity.

What is a centripetal force? a force that acts in a lot of directions at once a force in the vertical direction a force that causes the speed of an object to increase or decrease a force that is directed sideways to the direction of motion

a force that is directed sideways to the direction of motion

What is the muon decay experiment? a real experiment a gedanken

a real experiment

Which of the following choices would be third in size, if you were to rank them from smallest to largest? galaxy quark cell person molecule solar system

cell

When two objects of like charge get nearer to each other, the strength of the repulsive force between them does what? becomes reversed gets smaller gets larger doubles in magnitude and becomes attractive remains the same

gets larger

If two protons were sitting side-by-side very close together (about 10-15 m apart), which of the following forces would be the weakest? electromagnetic nuclear weak force nuclear strong force gravity

gravity

The electric force ________ with increasing charge. decreases increases

increases

The gravitational force ________ with increasing mass. decreases increases

increases

Two objects are attracted to each other by gravitational forces. Suppose I double the mass of one of the objects. This changes the gravitational forces between them. I can make this force the same as it was at first, however, by doing what? doing nothing—the force is not changed unless I change the mass of both objects, since the gravitational force depends on both these masses decreasing the distance between the objects and increasing the mass of the other object increasing the distance between the two objects increasing the mass of the other object decreasing the distance between the two objects

increasing the distance between the two objects

Which of the following quantities is conserved in non-relativistic processes? time length pressure mass force

mass

Two events that are observed to be simultaneous in one reference frame are _________ simultaneous if observed in another frame if two observers are both in uniform motion. always not necessarily

not necessarily

The Moon is moving around the Earth with constant speed in a nearly circular orbit. What forces are acting on the moon? a gravitational force balanced by the centrifugal force just a centrifugal force one unbalanced gravitational force one force keeping the moon moving and another force keeping it in orbit

one unbalanced gravitational force

The figure shows the position of a car at equal time intervals. In which of the pictures below is the kinetic energy of the car increasing? all of them picture 1 picture 2 picture 3 picture 4

picture 1

Scientists assume that physical laws are the same on earth and on Alpha Centauri, the closet star to our sun visible with the naked eye. This is an example of time symmetry sensory data and authority insanity causality position symmetry

position symmetry

Which of the following particles are positively charged? neutron proton electron

proton

Your roommate asks you to taste the milk in the refrigerator to see if it is sour. What source of knowledge is he asking you to rely on? principle of non-contradiction existence reason sensory data intuition

sensory data

Select all correct answers. What are the ways of obtaining knowledge, according to the textbook? sensory data intuition authority reason

sensory data intuition authority reason

A distant star is moving toward the earth at a speed of 1/4 the speed of light. Compared to the light from a flashlight on the earth, the speed of the light from the star would be moving how fast? the same 1 3/4 times as fast 1/4 as fast 1 1/4 times as fast 3/4 as fast

the same

For two observers in inertial reference frames that are moving away from each other, the laws of nature are different. the same.

the same.

The light clock experiment is a thought experiment that illustrates which of the following? anomalous dispersion length expansion time dilation motion symmetry mass increase

time dilation

The principle of uniformitarianism is used by geologists and assumes that past geologic events can be explained by natural processes that are observed today. This principle is an example of which self-evident truth? time symmetry non-contradiction reason position symmetry

time symmetry

Now the elevator and the girl standing on the scale are mid-floor and are moving at a constant speed upward. Which choice properly describes her weight, contact force, and acceleration at this point? weight = 130 lbs downward, contact force = 130 lbs upward, acceleration is zero weight = 130 lbs downward, contact force = 130 lbs upward, acceleration is downward weight = 130 lbs downward, contact force = 130 lbs upward, acceleration is upward weight = 140 lbs downward, contact force = 130 lbs upward, acceleration is downward weight = 140 lbs downward, contact force = 130 lbs upward, acceleration is upward weight = 130 lbs downward, contact force = 140 lbs upward, acceleration is upward weight = 130 lbs downward, contact force = 140 lbs upward, acceleration is downward

weight = 130 lbs downward, contact force = 130 lbs upward, acceleration is zero

A girl stands in an elevator on a scale as the elevator just begins to move upward. Which choice properly describes her weight, contact force, and acceleration at this instance? weight = 130 lbs downward, contact force = 130 lbs upward, acceleration is zero weight = 130 lbs downward, contact force = 130 lbs upward, acceleration is downward weight = 130 lbs downward, contact force = 130 lbs upward, acceleration is upward weight = 140 lbs downward, contact force = 130 lbs upward, acceleration is downward weight = 140 lbs downward, contact force = 130 lbs upward, acceleration is upward weight = 130 lbs downward, contact force = 140 lbs upward, acceleration is upward weight = 130 lbs downward, contact force = 140 lbs upward, acceleration is downward

weight = 130 lbs downward, contact force = 140 lbs upward, acceleration is upward

Can one detect the rotation of the Earth on its axis in any way? yes no

yes

In a certain nuclear reaction, a radioactive nucleus with a net charge of +6 decays, emits an electron (-1 charge) and a neutrino (no charge), and turns into a nucleus that has a net charge of which of the following choices? (Hint: Think about Conservation of Charge. Drawing a picture may help.) -1 +1 +5 -6 +6 +7

+7

A free neutron (no charge) can decay into a proton (charge of +1), a neutrino (no charge), and one other particle. What does the charge of the other particle need to be? -1 +1 -2 0 +2

-1

10-5 is the same number as 0.00001 100,000. None of the above I have no clue what this notation means.

0.00001

An automobile is traveling in a circle. Which of the following must be true? There is at least one unbalanced force on it. The forces on it are balanced. The net force is zero. It is not accelerating. There do not need to be any forces on it. It is not changing its speed.

There is at least one unbalanced force on it.

According to the second postulate of the Special Theory of Relativity, the speed of light is _______ the same for two observers moving away from each other. sometimes always never

always

The gravitational force can either attract or repel objects with mass always repels objects with mass always attracts objects with mass

always attracts objects with mass

What direction is the buoyant force that a fluid exerts on a submerged object? upward if the object floats always down downward if the object sinks always up

always up

The gravitational force ________ with increasing distance. decreases increases

decreases

Which of the following describes electrical potential energy? depends on the density and buoyant force depends on the mass and speed depends on temperature depends on the distance between charged particles depends on the mass and height

depends on the distance between charged particles

The force which holds atoms together to form molecules is called the electromagnetic force. molecular force. strong force. gravitational force. weak force.

electromagnetic force.

Which of the following particles are negatively charged? proton electron neutron

electron

Which of the following particles are found around the outside of an atom and are easily transferred from one atom to another? neutrons positrons protons muons electrons

electrons

A medium-sized star is rotating about its axis (similar to how the Earth rotates about its axis once each day). At the end of its life, it collapses into something called a neutron star which has a much smaller radius than the original star. In the process, there are not forces which would, of themselves, speed up or slow down the rotation of the star. Considering conservation of angular momentum, we would expect the rotation speed of the star to do what? increase decrease stay the same increase or decrease

increase

When would you exert the most pressure on the floor? when you are wearing tennis shoes when you are wearing high-heeled shoes

when you are wearing high-heeled shoes