PHYS 105 Exam 1

foot

English unit

gallon

English unit

inch

English unit

mile

English unit

ounce

English unit

pound

English unit

cm

SI unit

cubic centimeter

SI unit

cubic meter

SI unit

gram

SI unit

kilogram

SI unit

kilometer

SI unit

meter

SI unit

velocity is a ____________ quantity

vector

Tectonic plates are large segments of the Earth's crust that move slowly. Suppose that 1 plate has an avg speed of 5 cm/year. What distance does it move in 1 second at this speed?

1.59 nanometers in 1 second

What are all the applications of physics in the biological sciences?

1. helps describe the properties of cell walls and membranes 2. explains the dynamics of the human body 3. Medical diagnostic tools (X-rays, MRI, etc.) and treatments (radiotherapy) are based on physics 4. explains sensory phenomena involving sound waves and visible light

In what situations would it be better to use SI units?

1. in deriving new units from fundamental units of length, time, and mass 2. in describing either very large or very small physical quantities

What must be met in order for the laws of classical physics to apply?

1. involving objects of size large enough to be seen with a microscope 2. involving speeds much less than the speed of light

What SI units are considered fundamental units, not derived units?

1. kg 2. second 3. meter

A box of mass 52 kg sits on a wooden floor. Tommy comes along and tries to push the box horizontally. Eventually, Tommy is able to overcome the friction force and move the box. As Tommy pushes the box with a force of 104 N, the box slides at a constant speed. What is the magnitude of friction force?

104 N

What is 65 mph in kilometers per hour?

104.585 km/hr

A box of mass 52 kg sits on a wooden floor. Tommy comes along and tries to push the box horizontally. When Tommy stops pushing, the box starts to slow down. Assuming nothing else has changed from (b) above, at what rate does the box slow down? Give the magnitude of acceleration.

2 m/s^2

What is 65 mph in meters per second?

29.05 m/s

Suppose that an astronaut can jump, in full astronaut gear, to a height of 0.55 m on the Earth. Given that the gravitational acceleration on the Moon is 1/6th of g on Earth, how high could this astronaut jump on the Moon?

3.3 meters on the moon

You can estimate how far away a thundercloud is by counting the amount of time that passes between when you see the flashes of lightning and when you hear the thunder sound. Assuming sound travels at 340 m/s, if you hear the thunder 9 seconds after you see the lightning, how far did the sound travel?

3.06 km

A box of mass 52 kg sits on a wooden floor. Tommy comes along and tries to push the box horizontally. When the box slides onto the part of floor that is made of marble, its acceleration changes to 0.800 m/s2. What is the magnitude of kinetic friction force on the box?

41.6 N

Tectonic plates are large segments of the Earth's crust that move slowly. Suppose that 1 plate has an avg speed of 5 cm/year. What is its speed in kilometers per million years?

50 km/million-year

The severity of a fall depends on your speed when you strike the ground. All factors but the acceleration due to gravity being the same, how many times higher could a safe fall on the Moon be than on Earth? That is, given that gravitational acceleration on the Moon is about 1/6 that of the Earth, if you could jump safely down from 1 meter height on the Earth, from how high a height (in meters) could you jump down from on the Moon without risking injury?

6x the height

Mt. Everest, at 29,028 ft, is the tallest mountain on Earth. What is its height in km?

8.84 km

American football is played on a 100-yd long field, excluding the end zones. How long is the field in meters?

91.44 meters

Newton's 1st and 2nd Laws say that external force is needed to produce acceleration, not velocity. Newton's 1st Law in particular says that an object in motion tends to stay in motion, unless external force acts on the object. But your everyday experience tells you that when you push something to move it (push a shopping cart, kick a soccer ball, slide a book on a table, etc.), it will come to a stop unless you continue to push it. Explain, with at least 2 examples, how Newton's 1st and 2nd Laws are correct and what detail needs to be taken into account.

Based on Newton's 1st/2nd Laws, motion of an object does not change unless force is acted upon it. The force that is necessary to move an object is influenced by the mass and in turn influences the acceleration and motion of an object. When an object is heavy and is forced to move, it goes slower compared to one w/ a lighter mass

Law of Acceleration

Newton's 2nd Law

Which Law of Motion? It takes an external force to start and to stop motion.

Newton's First Law

Law of Attraction Between Masses

Newton's Law of Universal Gravitation

Which Law of Motion? Acceleration is proportional to force and inversely proportional to mass, or inertia

Newton's Second Law

Which Law of Motion? In ball sports, there is an inverse relationship between typical max speed of a ball and its mass

Newton's Second Law

Which Law of Motion? A rocket is propelled forward (both within atmosphere and in space) by ejecting fuel exhaust backward

Newton's Third Law

Which Law of Motion? An astronaut in spacewalk can be stranded in outer space, if they are separated from the tether even by a small distance without a jetpack

Newton's Third Law

Which Law of Motion? On a boat floating on a calm lake, no amount of pushing within the boat will move the boat and its occupants in one overall direction.

Newton's Third Law

Which Law of Motion? Whenever a force is exerted, they are exerted in a pair of forces of equal magnitude, each acting on a different object

Newton's Third Law

Law of Inertia

Newton's first law

Law of Interaction

Newton's third law

Name 2 revolutionary theories that constitute modern physics

Relativity, quantum mechanics

scalar quantity

a quantity that can be described by magnitude only and has no direction

vector quantity

a quantity that has both magnitude and direction

A jogger running at 5 m/s starts running up a small hill, slowing down at an average rate of 0.2 m/s^2 for the next 2 seconds while going to the top of the hill. As they reach the top of the hill, how fast is the jogger running? Choose the closest answer. a. 4.6 m/s b. 3.8 m/s c. 4.2 m/s d. 3.0 m/s e. 3.4 m/s

a. 4.6 m/s

Consider a cannon that can fire a cannonball at a certain speed at angles ranging from 0-90 degrees above the horizontal. If the initial speed of the cannonball remains the same as you vary the angle of the cannon, at what angle do you need to fire the cannonball so that it will reach the maximum range possible? a. 45 degrees b. 90 degrees c. 15 degrees d. 75 degrees

a. 45 degrees

Consider a rock thrown directly upward at 30 m/s. Use approximate value g = 10 m/s^2 and ignore air resistance. What max height does the rock reach? a. 45 meters b. 80 meters c. 20 meters d. 5 meters e. 61 meters

a. 45 meters

Consider an elevator carrying a passenger as it accelerates upward. A number of different forces act on the elevator and the passenger. Choose the statement below which correctly identifies one pair of action and reaction forces and correctly identifies one of the external forces. (The diagram below shows forces, with numbers used in the statements below.) a. One action/reaction pair is "(2) downward normal force on elevator" and "(4) upward normal force on passenger"; one external force is "(1) upward tension force on elevator." b. One action/reaction pair is "(1) upward tension force on elevator" and "(3) downward weight on elevator"; one external force is "(4) upward normal force on passenger. c. One action/reaction pair is "(5) downward weight on passenger" and "(1) upward tension force on elevator"; one external force is "(3) downward weight on elevator." d. One action/reaction pair is "(2) downward normal force on elevator" and "(1) upward tension force on elevator"; one external force is "(3) downward weight on elevator."

a. One action/reaction pair is "(2) downward normal force on elevator" and "(4) upward normal force on passenger"; one external force is "(1) upward tension force on elevator."

Your friend Sue claims that a car making a turn at a constant speed (of 40 mph, for example) is in fact "accelerating," in the sense used in physics classes (like this one). Which explanation below mostly correctly describes why your friend Sue is correct? a. Sue is correct bc when a car makes a turn moving at a constant speed (of 40 mph), its velocity is changing. An object is said to accelerate when its velocity changes b. Sue is correct bc you have insufficient evidence to disprove her claim. In science, all claims are presumed correct until proven incorrect and must be given a serious consideration c. Sue is correct because when the car makes a turn, you feel the centrifugal force pushing you to the outer edge of the turn. According to Newton's Second Law, F = ma, so you are accelerating due to the centrifugal force d. Sue is not correct. If a car moves at a constant speed (of 40 mph), then it is not speeding up or slowing down, so it is not accelerating

a. Sue is correct bc when a car makes a turn moving at constant speed (of 40 mph), its velocity is changing. An object is said to accelerate when its velocity changes

Consider physical scenarios given below and choose the situation in which the velocity is zero, but the acceleration is not zero. a. a ball that is thrown directly upward at the top of its trajectory b. a car moving down a straight section of freeway at a constant speed of 60 mph c. a car as it slows down to a stop, but before it has come to a complete stop d. a ball that is thrown across the field at the top of its trajectory

a. a ball that is thrown directly upward at the top of its trajectory

Choose the situations in which velocity is 0, but acceleration is not 0. a. a car starting up from rest b. a ball that is thrown across the field at the top of its trajectory c. a car moving down a straight section of freeway at constant speed of 60 mph d. a car as it slows down to a stop, but before it has to come to a complete stop e. a car that has to come to a complete stop and remains stopped f. a ball that is thrown directly upward at the top of its trajectory

a. a car starting up from rest f. a ball that is thrown directly upward at the top of its trajectory

Each statement below describes an everyday situation and cites Newton's Laws of motion most important/significant in explaining/describing the situation. Choose the most correct statement below a. a heavy object and a light object both fall w/ same gravitational acceleration in free-fall, bc of Newton's 1st and 2nd Laws b. you need to exert a greater force to lift a heavier object, bc of Newton's 3rd Law c. when you push a shopping cart, an empty cart speeds up quickly, while a loaded cart will not speed up as quickly, bc of Newton's 3rd Law d. when a ball hits you, it comes to a stop or bounces back, bc of Newton's 1st and 2nd Laws

a. a heavy object and a light object both fall with the same gravitational acceleration in free-fall, bc of Newton's 1st and 2nd Laws

Which of the following is NOT an example of projectile motion? a. a paper airplane thrown across the room b. a baseball being hit for a homerun c. a football thrown across the field d. a gymnast jumping off for a landing

a. a paper airplane thrown across the room

Choose the statement below which most correctly describes external and internal forces. a. acceleration of a body is most directly associated w/ net external force, w/out regard to internal forces b. external forces can change mechanical energy of a system while internal forces cannot c. external forces are exerted from the system onto its surroundings d. internal forces are forces acting into the system from outside

a. acceleration of a body is most directly associated w/ net external force, w/out regard to internal forces

Consider an object of mass 3 kg resting on a table. Choose the statement below which most correctly describes the forces on the object. Use g = 10 m/s^2 a. an upward normal force of 30 N acts on the object; the net force on the object is 0 N b. an upward normal force of 30 N acts on the object; the net force on the object is 30 N c. a downward normal force of 30 N acts on the object; a gravitational force of 30 N acts on the object d. the net force on the object is 30 N; a gravitational force of 0 N acts on the object

a. an upward normal force of 30 N acts on the object; the net force on the object is 0

Which of the following INCORRECTLY defines or describes "free-fall"? a. if an object is moving upward, it cannot be considered to be in a free-fall b. in free-fall motion, air and wind resistance are ignored. c. objects in free-fall are being affected only by gravity d. an object in free-fall is accelerating at gravitational acceleration

a. if an object is moving upward, it cannot be considered to be in a free-fall

Which of the following situations describe where acceleration is not 0? a. moving in a constant speed along a circle b. starting to move from rest c. speeding up or slowing down while moving d. moving at a constant speed in a straight line

a. moving in a constant speed along a circle b. starting to move from rest c. speeding up or slowing down while moving

Upward direction is + for this question. For a rock thrown straight upward, the acceleration is (A)_____________ on the way up. The acceleration of this rock is (B)___________ at the top of its flight. The acceleration of this rock is (C)___________ on the way down.

a. negative b. negative c. negative

Consider the gravitational force between Earth and an apple that falls from a tree. Evaluate the following statements and choose the INCORRECT statement a. the gravitational acceleration of the apple is equal in magnitude to the gravitational acceleration of the Earth b. the magnitude of gravitational force on the apple by the Earth is equal to the magnitude of gravitational force on the Earth by the apple c. the acceleration of the apple due to gravitational force on the apple is greater than the acceleration of the Earth due to gravitational force on the Earth d. the gravitational force on the apple by the Earth is in opposite direction from the gravitational force on the Earth by the apple

a. the gravitational acceleration of the apple is equal in magnitude to the gravitational acceleration of the Earth

A rock is thrown straight up. What is the net external force acting on the rock when it is at the top if its trajectory? a. the net external force is directed downward and equal to the weight of the rock b. there is not enough info to answer this question c. the net external force is 0 d. the net external force is directed upward and equal to the weight of the rock

a. the net external force is directed downward and equal to the weight of the rock

Consider an elevator carrying a passenger. If the elevator is moving upward at a constant speed, how does the magnitude of normal force on the passenger compare with the magnitude of passenger's weight? a. the normal force is equal to the weight b. the answer depends on how large the upward speed is c. the normal force is less than the weight d. the normal force is greater than the weight

a. the normal force is equal to the weight

You can measure your own reaction w/ a simple experiment. W/ a helper holding a ruler vertically, you have them drop the ruler w/out a notice and try to grab the ruler as quickly as you can. The distance that the ruler falls through before you are able to catch can be related to your reaction time. If in an experiment like this one, the ruler falls through 30 cm, what is your reaction time in seconds? Choose the closest answer below. a. the reaction time is 0.24 second for falling distance of 30 cm b. the reaction time is 0.14 second for falling distance of 30 cm c. the reaction time is 0.32 second for falling distance of 30 cm d. the reaction time is 0.28 second for falling distance of 30 cm e. the reaction time is 0.20 second for falling distance of 30 cm.

a. the reaction time is 0.24 second for falling distance of 30 cm

For projectile motion on level ground assuming negligible air resistance for a launch angle between 1-89 degrees: The velocity of the projectile is at minimum at (A)_____________, and the velocity of the projectile is at a max at (B)___________________.

a. the top b. the point of launch

Each statement below describes an everyday situation and cites a Newton's Law of Motion most important/significant in explaining/describing the situation. Choose the most correct statement. a. when the wheels of an automobile spin in the forward direction, the car rolls forward, because of Newton's 3rd Law b. a car moving 2x as fast needs 4x as much braking distance, all other things being equal, bc of Newton's 1st Law c. to move away from your desk while sitting on a rolling chair, you push the desk away form you, bc of Newton's 2nd Law d. a jump from a higher height has a greater risk of injury than a jump from a lower height, bc of Newton's 3rd Law

a. when the wheels of an automobile spin in the forward direction, the car rolls forward, bc of Newton's 3rd Law

How is chemistry related to physics?

atomic and molecular physics

Selma pulls a sofa to move it across the room. While she pulls on the sofa w/ force of 450 N, a friction force of 300 N acts on the sofa. The sofa's mass is 90 kg. What is the acceleration of the sofa while Selma pulls on it? Give your answer in meters/second^2 a. 3.33 m/s^2 b. 1.67 m/s^2 c. 6.67 m/s^2 d. 5.00 m/s^2

b. 1.67 m/s^2

How is engineering related to physics?

applied physics

Choose the statement below which most correctly categorizes the lists of examples of forces and not forces. a. "push of a baseball bat on the ball", "pull of a stretched spring", and "Earth" are forces; "Sun", "jumping off a wall", and "home-run ball flying off from bat" are not forces. b. "Pull of a stretched spring", "push of a foot on the ground", and "push of a baseball bat on the ball are forces, "home-run ball flying off from bat", "gymnast sticking a landing", and "acceleration of a speeding car" are not forces. c. "gymnast sticking a landing", "Earth", and "push of a baseball bat on the ball" are forces; "jumping off a wall", "push of a foot on the ground", and "pull of a stretched spring" are not forces d. "jumping off a wall", "push of a baseball bat on the ball", and "home-run ball flying off from bat" are forces; "Earth", "gymnast sticking a landing", and "Sun" are not forces

b. "Pull of a stretched spring", "push of a foot on the ground", and "push of a baseball bat on the ball" are forces; "home-run ball flying off from bat", "gymnast sticking a landing", and "acceleration of a speeding car" are not forces

What is the acceleration of a projectile in the horizontal direction? a. 10 m/s^2 b. 0 m/s^2 c. 9.8 m/s^ d. depends on the launch angle

b. 0 m/s^2

Choose all situations below which illustrate the physics concept of "Inertia" a. a large shipping vessel comes to a stop when its engines are turned off b. a bowling ball placed on a level, smooth ground remains at rest until pushed c. a bowling ball rolling on a level, smooth ground rolls a long distance d. Voyager probes, launched in 1970s to study the outer solar system, are continuing to fly away from the Sun into the interstellar space today

b. a bowling ball placed on a level, smooth ground remains at rest until pushed c. a bowling ball rolling on a level, smooth ground rolls a long distance d. Voyager probes, launched in 1970s to study the outer solar system, are continuing to fly away from the Sun into the interstellar space today

Which of the following most correctly describes why models are useful in physics? a. a model describes nature more accurately than the complicated reality can b. a model aids in calculation of a physical phenomenon c. a model is a unique representation of the underlying physical reality d. a model helps reveal previously undiscovered law of physics

b. a model aids in calculation of a physical phenomenon

Which of the following statements below most correctly describes or defines "vector", "magnitude", or "scalar"? a. magnitude is a unitless quantity of length b. a vector is a physical quantity w/ both magnitude and direction c. a vector is a quantity w/ magnitude but no direction d. a scalar is the size of a physical quantity

b. a vector is a physical quantity w/ both magnitude and direction

Choose the correct description and/or property of force below. a. force is necessary to keep an object moving b. force is necessary to move an object at rest c. acceleration causes force d. force is an energy field created by all living things

b. force is necessary to move an object at rest

Physics has many applications in the biological sciences. Choose the correct description of application of physics in the biological sciences. a. explains how organic compounds are different from inorganic compounds b. helps describe the properties of cell walls and membranes c. explains the processes that occur in our brain to form memories and feel emotions d. differentiates energy in living beings from mechanical energy

b. helps describe the properties of cell walls and membranes

If the acceleration of a system is 0, choose the statement which most correctly describes forces acting on this system. a. there is a force on the system only if it is already moving b. if there are 2 forces acting on the system, the 2 forces are opposite in directions and equal in magnitudes c. no force acts on the system d. the net force on the system is less than the weight of the system

b. if there are 2 forces acting on the system, the 2 forces are opposite in directions and equal in magnitudes

Each statement below describes an everyday situation and cites a Newton's Laws of Motion most important/significant in explaining/describing the situation. Choose the most correct statement below a. a rocket is propelled forward (both in atmosphere and in space) by ejecting fuel exhaust backward, bc of Newton's 2nd Law b. in ball sports, there is an inverse relationship between typical max speed of a ball and its mass, bc of Newton's 2nd Law c. an astronaut in spacewalk can be stranded in outer space, if they are separated from the tether even by a small distance w/out a jetpack, bc of Newton's 2nd Law d. on a boat floating on a clam lake, no amount of pushing within the boat will move the boat and its occupants in one overall direction, bc of Newton's 1st Law

b. in ball sports, there is an inverse relationship between typical max speed of a ball and its mass, bc of Newton's 2nd Law

Which of the following statement correctly defines or describes inertia? a. inertia is the tendency of objects to be at rest b. inertia is a measure of how much force is needed to produce a fixed amount of acceleration c. inertia is a measure of how heavy a given object is and how much force is needed to lift it. d. inertia is a type of force inherent in every object

b. inertia is a measure of how much force is needed to produce a fixed amount of acceleration

Choose the statement below which most correctly distinguishes between a force and the net force a. the gravitational acceleration is a type of net force b. net force is the sum of all forces on an object, w/ the directions in mind c. if the net force is 0, that means that no force acts on the object d. the net force is a type of force distinct from normal force or tension force

b. net force is the sum of all forces on an object, w/ the directions in mind

Is it possible for velocity to be constant while acceleration is not zero? a. yes, w/ non-zero acceleration, velocity could remain constant b. no, with non-zero acceleration, velocity must change c. it depends on additional circumstances

b. no, with non-zero acceleration, velocity must change

If you use the same launch angle and initial speed when launching an object of your choice, how does it affect the motion? a. the projectile travels further if its mass is smaller b. the motion stays the same, regardless of the mass and size of the object c. the projectile travels further in its size (diameter) is smaller d. the answer varies on the value of initial velocity e. the answer varies based on the value of the launch angle

b. the motion stays the same, regardless of the mass and size of the object

Consider the following scenario in application of Newton's Laws. A box of mass 55 kg sits on a wooden floor. Tommy comes along and tries to push the box horizontally. As Tommy tries to push the box with a force of 21 N, the box won't budge. What is the net force on the box? a. the net force on the box is -21 N. b. the net force on the box is 0 N c. the net force on the box is 550 N d. the net force on the box is 21 N

b. the net force on the box is 0 N

If you launched an object at 90 degrees and kept all other parameters the same, but decreased the value of the acceleration due to gravity, what happens to the motion of the object? a. the object's motion does not change b. the object reaches a greater max height c. the object reaches a smaller max height

b. the object reaches a greater max height

Choose the statement which matches one of Newton's Laws w/ the short description correctly. a. "Newton's First Law of Motion" may be called "Law of Acceleration" b. "Newton's Law of Universal Gravitation" may be called "Law of Acceleration" c. "Newton's 3rd Law of Motion" may be called "Law of Interaction" d. "Newton's Law of Universal Gravitation" may be called "Law of Inertia"

c. "Newton's 3rd Law of Motion" may be called "Law of Interaction"

A cyclist rides along a straight road w/ an average velocity of 8 m/s for 2 minutes. How far does the cyclist ride in this time? Choose the closest answer. a. 1.4 km b. 0.5 km c. 1.0 km d. 1.2 km e. 0.7 km

c. 1.0 km

A car going at 35 mph (about 16 m/s) comes to a sudden stop, slowing down at 10 m/s^2. How far does the car move forward before eventually coming to a stop? a. 9 meters b. 16 meters c. 12 meters d. 6 meters e. 4 meters

c. 12 meters

Suppose that an astronaut can jump, in full gear, to a height of 0.5 m on the Earth. Given that the gravitational acceleration of the Moon is 1/6th of g on Earth, how high could this astronaut jump on the Moon? Choose the closest answer. a. 0.1 m b. 0.5 m c. 2.0 m d. 1.0 m e. 18.0 m

c. 3.0 m

If you use the same object and initial speed when launching an object from your choice of launch angle, what angle gives you the max range? a. 90 degrees b. 60 degrees c. 45 degrees d. 30 degrees

c. 45 degrees

Jane is riding in an elevator that is starting to move upward. She is standing on a scale so that she can measure her apparent weight as the elevator moves upward. Before the elevator starts to move upward, Jane, whose mass is 70 kg reads 700 Newtons on the scale. As the elevator accelerates upward at 2 m/s^2, what does Jane read on the scale she is standing on? a. 700 N b. 140 N c. 840 N d. 686 N

c. 840 N

Which of the following statements below most correctly describes or defines what a physical law, model, or theory is? a. a model is a concise description of the natural world b. a model is an explanation for patterns in nature c. a theory is an explanation for patterns in nature d. a law is a representation of a natural system which aids in explanation or calculation

c. a theory is an explanation for patterns in nature

During a lecture demonstration, a professor places two coins on the edge of a table. She then flicks one of the coins horizontally launching it off the table, simultaneously nudging the other just over the edge. Which of these two coins hit the floor first? a. the coin that is nudges just over the edge hits the floor first b. the coin that is launched horizontally off the table hits the floor first c. both coins hit the floor at the same time

c. both coins hit the floor at the same time

Consider the following scenario in application of Newton's Laws: A box of mass 56 kg sits on a wooden floor. Tommy comes along and pushes the box horizontally. After the box has been sliding for a while, Tommy stops pushing, and the box slows down w/ acceleration of magnitude 0.600 m/s^2. What is the magnitude of kinetic friction force on the box? a. the magnitude of kinetic friction force is 56 n b. the magnitude of kinetic friction force is 560 N c. the magnitude of kinetic friction force is 34 N d. none of the above

c. the magnitude of kinetic friction force is 34 N

The so-called zero-g airplane (sometimes called "vomit comet") flies in parabolic arcs to provide sensation of weightlessness to its passengers for brief periods of time (about 20 seconds). Along some of these parabolic arcs, as the airplane pulls up, the passengers feel not weightlessness but a sensation of "hypergravity," where they feel heavier than usual (often so heavy that it is difficult for the passengers to stand or sit upright). What happens to the passengers during these periods of hypergravity? a. during these periods of hypergravity, the mass of the passengers increase to match the heavier feel b. during these periods of hypergravity, the weight of the passengers increase to match the increase in apparent weight c. during these periods of hypergravity, the floor of the airplane exerts an upward force on the passengers, accelerating them upward and making them feel heavier d. during these periods of hypergraity, the zero-g airplane is closest to Earth, which makes the gravitational pull of Earth stronger

c. during these periods of hypergravity, the floor of the airplane exerts an upward force on the passengers, accelerating them upward and making them feel heavier.

Physics has many applications in the biological sciences. Choose the INCORRECT description of application of physics in the biological sciences. a. explains sensory phenomena involving sound waves and visible light b. explains the dynamics of the human body c. explains the processes that occur in our brain to form memories and feel emotions d. medical diagnostic tools (X-ray, MRI, etc.) and treatments (radiotherapy) are based on phsyics. e. helps describe the properties of cell walls and membranes

c. explains the processes that occur in our brain to form memories and feel emotions

Consider a rocket being launched into space. If we call the thrust lifting the rocket upward the "reaction force," which of the following is the action force pair to this reaction force? a. gravitational force pulling the rocket downward b. force of the combustion pushing the air downward c. force on the rocket fuel combustion products being pushed downward d. force of the combustion pushing the ground downward

c. force of the rocket fuel combustion products being pushed downward

When you take off in a commercial jet airplane, there is a sensation of being pushed backward into your seat. Which of the following is NOT a real force acting on you at this moment? a. upward push of seat bottom b. forward push of the seat back c. forward push due to velocity d. downward pull of gravity

c. forward push due to velocity

Which of the following INCORRECTLY defines "free-fall"? a. an object in free-fall is accelerating at gravitational acceleration b. in free-fall motion, air and wind resistance are ignored. c. if an object is moving upward, it cannot be considered to be in a free-fall d. objects in free-fall are being affected only by gravity

c. if an object is moving upward, it cannot be considered to be in a free-fall

As two boys are playing in the outdoors, one boy hangs from a tree while the other boy aims a water balloon cannon directly at him. Choose the statement below which most correctly predicts what will happen in the next moment, depending on what the boy who hangs from the tree decides to do. a. if the boy lets go off the tree the moment the water balloon is fired, the boy will avoid getting hit by the water balloon, as the cannon was aimed directly where he was b. if the boy continues to hold onto the tree, he will get hit by the water balloon, as the cannon is aimed directly at him c. if the boy lets go of the tree the moment the water balloon is fired, the boy will definitely get hit by the water balloon, as the water balloon's trajectory curves downward along w/ the falling boy d. if the boy continues to hold onto the tree, he will definitely avoid getting hit by the water balloon, as the water balloon will curve downward and hit the tree below boy's feet.

c. if the boy lets go of the tree the moment the water balloon is fired, the boy will definitely get hit by the water balloon, as the water balloon's trajectory curves downward along w/ the falling boy

Choose the choice which most correctly completes this sentence: "In order for the laws of classical physics to apply, it is necessary to have situations..." a. involving phenomena that occur in the solar system b. involving speeds much less than the speed of sound c. involving speeds much less than the speed of light d. involving objects of size large enough to be seen w/ naked eyes e. involving phenomena that occur in the Milky Way galaxy

c. involving speeds much less than the speed of light

Choose the quantity of unit below which is an SI unit a. foot b. gallon c. kilometer d. ounce e. inch

c. kilometer

Which of the following is a valid unit for acceleration? a. m/s b. horsepower c. m/s^2 d. m^2/s^2

c. m/s^2

Which of the following situations describes where acceleration is zero? a. speeding up or slowing down while moving b. starting to move from rest c. moving at a constant speed in a straight line d. moving in a constant speed along a circle

c. moving at a constant speed in a straight line

Physics is the foundation of many important disciplines and contributes directly to others. Which of the following correctly lists geology's relation to physics? a. atomic and molecular physics b. structural stability, acoustics, heating, lighting, and cooling c. radioactive dating, earthquake analysis, and heat transfer d. applied physics

c. radioactive dating, earthquake analysis, and heat transfer

Consider an ideal spring which obeys Hooke's Law perfectly. When a force of 1 N is applied to the spring, the spring stretches by 2 cm. How much does it stretch by, when a force of 1.4 N is applied? a. stretches by 3.2 cm when a force of 1.4 N is applied b. stretches by 0.8 cm when a force of 1.4 N is applied c. stretches by 2.8 cm when a force of 1.4 N is applied d. stretches by 1.6 cm when a force of 1.4 N is applied e. stretches by 2.4 cm when a force of 1.4 N is applied

c. stretches by 2.8 cm when a force of 1.4 N is applied

A car accelerates from rest at constant acceleration. Which of the following correctly describes the distance traveled by the car? a. the distance traveled increases linearly w/ the time b. the car travels the same distance form time 1 to 2 seconds as it did from time 0 t 1 second c. the distance traveled increases w/ square of the time d. the car travels double the distance from time 1 to 2 seconds as it did from time 0 to 1 second

c. the distance traveled increases with square of the time

Consider an object of mass 5 kg resting on a table. Choose the statement below which most correctly describes the forces on the object. Use g≈10 m/s2g≈10 m/s2. a. the net force on the object is 50N; a gravitational force of 0N acts on the object b. a downward normal force of 50N acts on the object; the net force on the object is 0 N c. the net force on the object is 0N; a gravitational force of 50N acts on the object d. a gravitational force of 50N acts on the object; a downward normal force of 50N acts on the object

c. the net force on the object is 0N; a gravitational force of 50N acts on the object

Which of the following completes this sentence w/ a generally correct fact? "At the top of a projectile motion..." a. the acceleration of the projectile is - b. the velocity of the projectile is 0 c. the projectile is accelerating downward at g d. the velocity vector of the projectile points downward

c. the projectile is accelerating downward at g

Suppose you throw a rock nearly straight up. Neglecting air resistance, how does the speed of the rock on the way up compare w/ the speed of the rock on the way down? a. the speed of the rock on the way up is faster compared to the speed of the rock on the way down b. the speed of the rock on the way down is faster compared to the speed of the rock on the way up c. the speed of the rock on the way up is equal to the speed of the rock on the way down d. which speed is faster (on the way up or on the way down) depends on additional parameters not specified above

c. the speed of the rock on the way up is equal to the speed of the rock on the way down

If a constant, non-zero net external force is applied to an object, which of the following statements regarding the velocity and the acceleration of the object is the most correct? a. the velocity and the acceleration of the object are changing b. the velocity and the acceleration of the object are constant c. the velocity of the object is changing and the acceleration is constant d. the velocity of the object is constant and the acceleration is changing

c. the velocity of the object is changing and the acceleration is constant

For this question, let the right direction be positive (+) and the left direction be negative (-). If a bird flies to the right while speeding up, which of the statements below correctly describes the signs of velocity and acceleration? a. velocity is + and acceleration is - b. velocity is - and acceleration is + c. velocity and acceleration are both + d. velocity and acceleration are both -

c. velocity and acceleration are both +

Which of the following statements correctly describes or defines "velocity"? a. velocity is given by acceleration b. velocity is the speed of motion c. velocity is the rate of change of position d. velocity is how fast something is moving

c. velocity is the rate of change of position

Can classical physics be used to accurately describe a satellite moving at a speed of 10000 m/s? a. no b. additional info needed c. yes

c. yes

Suppose you are holding a meter stick, a ruler that is one meter long, which is marked on one side in cm and on the other side in inches. As you look at the cm side, approximately how many marks do you see? Assume no marks smaller than a cm. a. 30 marks b. 1 mark c. 1000 marks d. 100 marks e. 300 marks

d. 100 marks

Which of the following most correctly describes why models are useful in physics? a. a model is a unique representation of the underlying physical reality b. a model describes nature more accurately than the complicated reality can c. a model helps reveal previously undiscovered law of physics d. a model represents something that cannot be shown directly

d. a model represents something that cannot be shown directly

Which of the following statements below most correctly describes or defines "vector", "magnitude", or "scalar"? a. a scalar is the size of a physical quantity b. magnitude is a unitless quantity of length c. a scalar is a physical quantity w/ both magnitude and direction d. a vector is a physical quantity w/ both magnitude and direction

d. a vector is a physical quantity w/ both magnitude and direction

Suppose Alice punches Bob in the face. If we call the force of Alice's fist on Bob's face the "action force", what is the correct reaction force paired to this action force? a. force of Bob punching Alice back b. the pain Bob feels on his face c. Bob being knocked out as a result of the punch d. force of Bob's face pushing back on Alice's fist

d. force of Bob's face pushing back on Alice's fist

For an accurate description of gravity, it is important to distinguish correctly between gravitational force and gravitational acceleration. Suppose you drop two masses, one 1 kg mass and another 10 kg mass. Choose the most correct statement below. a. gravitational acceleration of 10 kg mass due to its weight is 10x the gravitational acceleration of 1 kg mass due to its weight b. weight of an object is most directly related to the gravitational acceleration of the object c. gravitational force on 10 kg mass due to Earth is equal to the gravitational force on 1 kg mass due to Earth d. gravitational force on 10 kg mass due to Earth is 10x the gravitational force on 1 kg mass due to Earth

d. gravitational force on 10 kg mass due to Earth is 10x the gravitational force on 1 kg mass due to Earth

Choose the unit of speed below that is the basic SI unit of speed. a. Kilometers per hour b. leagues per day c. miles per hour d. meters per second

d. meters per second

Timmy has fallen in a well! Firefighters are rescuing Timmy by securing him to a harness and pulling him upward. Timmy considers his situation as he is being pulled upward at a steady speed. Which statement below most correctly compares the tension force pulling him up with Timmy's weight pulling him downward? a. additional info is needed to compare tension force to Timmy's weight b. tension force is less than Timmy's weight c. tension force is greater than Timmy's weight d. tension force is equal to Timmy's weight

d. tension force is equal to Timmy's weight

Except for projectile motion launched at a 45 degree angle, a given range can be reached by projectiles launched w/ the same initial speed but at 2 different angles. Choose the statement below which most correctly contrasts these 2 different trajectories. a. the trajectory launched at the higher angle reaches the landing position more quickly b. the projectile launched at the smaller angle must be launched at a larger initial speed in order to reach the same range c. both projectiles follow trajectories that are identical in every aspects except for initial launch angles d. the projectile launched at the smaller angle spends less time in the air

d. the projectile launched at the smaller angle spends less time in the air

"Recoil" describes a sensation of being pushed backward, for example, when one fires a rifle. Recoil is also experienced in launching other projectiles, such as a cannon firing a cannonball. Why does recoil happen? a. the recoil happens bc of Newton's 1st Law. A (would-be) projectile at rest tends to stay at rest, and the result of the projecting this projectile is that the projector is pushed backward b. the recoil happens only for a rifle or cannon that is not adjusted properly (the bullet or cannonball fits too tightly in the barrel). With proper adjustment, the recoil can be greatly reduced or eliminated. c. the recoil happens bc of conservation of energy. The projectile has more energy when it is moving than when it's not, so the recoil is felt as the projector loses some energy. d. the recoil happens bc of Newton's 3rd Law, and the sensation of being pushed backward is due to the reaction force

d. the recoil happens bc of Newton's 3rd Law, and the sensation of being pushed backward is due to the reaction force

you can estimate how far away a thundercloud is by counting the amount of time that passes between when you see the flashes of lightning and when you hear the thunder sound. Assuming sound travels at 340 m/s, if you hear the thunder 8 seconds after you see the lightning, how dar did the sound travel? a. the sound of thunder traveled 3.4 km b. the sound of thunder traveled 0.7 km c. the sound of thunder traveled 1.4 km d. the sound of thunder traveled 2.7 km e. the sound of thunder traveled 2.0 km

d. the sound of thunder traveled 2.7 km

Suppose you observe an object moving from left to right. What additional information, if any, do you need to determine the direction of the acceleration of the object? a. to determine the direction of the acceleration of the object, you need to know its mass b. to determine the direction of the acceleration of the object, you need to know how fast the object was moving c. there is already sufficient info to determine the direction of acceleration, from left to right d. to determine the direction of acceleration of the object, you need to know how the speed of the object was changing (increasing or decreasing)

d. to determine the direction of acceleration of the object, you need to know how the speed of the object was changing (increasing or decreasing)

For projectile motion on level ground assuming negligible air resistance for a launch angle between 1-89 degrees: The speed of the projectile on the way down, as it reaches the height where it was launches, its speed is ______________ its speed as it was launched

equal to

an airplane flies at a constant cruising speed of 700 mph

forward force equal to backward force

an automobile on cruise control moves at a constant speed of 65 mph along a straight freeway

forward force equal to backward force

An airplane speeds up along runway as it prepares to take off

forward force greater than backward force

an airplane successfully lands at the destination airport

forward force less than backward force

What does MRI stand for?

magnetic resonance imaging

What is the basic SI unit of speed?

meters per second

For projectile motion on level ground assuming negligible air resistance for a launch angle between 1-89 degrees: Is acceleration ever 0?

no, acceleration is at a constant non-zero value throughout the motion

For projectile motion on level ground assuming negligible air resistance for a launch angle between 1-89 degrees: Is the acceleration ever in the same direction as the velocity?

no, not for any moment during the motion

For projectile motion on level ground assuming negligible air resistance for a launch angle between 1-89 degrees: Is velocity ever 0?

no, while the velocity varies, it never reaches 0

How is geology related to physics?

radioactive dating, earthquake analysis, and heat transfer

distance is a ________ quantity

scalar

speed is a ___________ quantity

scalar

temperature is a ________ quantity

scalar

How is architecture related to physics?

structural stability, acoustics, heating, lighting, and cooling

Consider the Earth, a table, and a book. The table is set on Earth, and the book is set on top of the table. List all the significant forces between these 3 objects (for each force, name the type of force, which object exerts the force, and on which object the force is; for example "gravitational force by Earth on the book") and Identify all the action/reaction force pairs (for example, "gravitational force by Earth on the book" and "gravitational force on the Earth by the book" are action/reaction force pairs)

the force of gravity of the Earth is pulling down the book and the force of the table (friction) pushing it upwards

A physicist friend of your says that when you are driving on a freeway at 60 mph following along a gentle curve, you are in fact "accelerating", even though you are neither speeding up nor slowing down but maintaining your constant speed of 60 mph. Explain how your physicist friend is using the word "acceleration" and come up w/ 1 more situation in which you are accelerating while moving at a constant speed.

this situation is considered a form of acceleration bc of the change in velocity. despite moving in a constant speed, the circular path actually affects the velocity of the car

force is a __________ quantity

vector

a passenger is riding on an elevator moving downward at a constant speed

upward force equal to downward force

a passenger is riding on an elevator moving upward at a constant speed

upward force equal to downward force

A passenger is riding on an elevator which is starting to move downward

upward force less than downward force

a passenger is riding on an upward-moving elevator which is coming to a stop

upward force less than downward force

displacement is a _____________ quantity

vector

For projectile motion on level ground assuming negligible air resistance for a launch angle between 1-89 degrees: Is the acceleration ever in a direction perpendicular to the velocity?

yes, for at least 1 moment during the motion