Preparing for tests Know when the test is! Make sure you leave time to study 24 hours before test–...

Preparing for tests•Know when the test is!

•Make sure you leave time to study

•24 hours before test– get good nights sleep. Don’t cram!

•Make sure you have all necessary supplies (pencil and calculator)

•Eat a good breakfast/lunch

•Try to exercise before a test

•Arrive early, review summary sheet, relax!

During Test•Listen carefully to all directions•Skim through entire test before you begin– budget your time•Go through entire test 3 times

•First time– answer all questions you know•Second time– answer all questions you can logically figure out•Third time– guess at the remaining answers

•Always read each question at least twice to completely understand its content•Take advantage of full time•Change answers only if you have a good reason to do so. Usually your first answer is right•Manage your anxiety

Multiple Choice Tests

•Choose your answer before you even look at the choices

•Read all choices before answering

•Use common sense in determining you answer

•Select the most correct answer

•Use answers from previous questions to help answer other questions

A student does an experiment to measure theacceleration of a falling object, which is9.8 m/s2 . The student obtains an experimentalvalue of 14.6 m/s2. The reason for this variationis most likely due to

A human error.B air resistance.C local fluctuations in gravity.D the mass of the object.

1

A student does an experiment to measure theacceleration of a falling object, which is9.8 m/s2 . The student obtains an experimentalvalue of 14.6 m/s2. The reason for this variationis most likely due toA human error.B air resistance.C local fluctuations in gravity.D the mass of the object.•Solve by process of elimination

•Unless you dropped a stone and a piece of paper, air resistance would not be a factor•Gravity does not fluctuate that much•Galileo showed mass does not affect rate

1

The picture shows two objects that were dropped and recorded with a stroboscopic camera. The best explanation for the results isthat object A

A has less air resistance.B was dropped from a greater height.C has a greater mass.D accelerated more slowly.

2

The picture shows two objects that were dropped and recorded with a stroboscopic camera. The best explanation for the results isthat object AA has less air resistance.B was dropped from a greater height.C has a greater mass.D accelerated more slowly. •A stroboscopic camera is an instrument that takes a picture at small time intervals•You can see they started at the same height•Mass does not affect the rate •Acceleration due to gravity is a constant 2

A student wires a series circuit that includes ablock of rubber and a light bulb. She states thatshe does not expect the light bulb to light upwhen current is applied to the circuit. Which ofthe following best describes her statement?

A It is a conclusion based on observed dataabout electrical phenomena.B It is a hypothesis based on knowledge of thetheory of electrical phenomena.C It is a procedure based on her hypothesisabout electrical phenomena.D It is a theory based on her observations ofelectrical phenomena 3

A student wires a series circuit that includes a block of rubber and a light bulb. She states that she does not expect the light bulb to light up when current is applied to the circuit. Which of the following best describes her statement?

A. It is a conclusion based on observed data about electrical phenomena.B. It is a hypothesis based on knowledge of the theory of electrical phenomena.C. It is a procedure based on her hypothesis about electrical phenomena.D. It is a theory based on her observations of electrical phenomena

3

A student applied a constant force to a toy truck. A graph of the truck’s movement is shown below. Which of the following could best explain the change in velocity at time X?

A. The truck’s momentum became greater than its inertia. B. The truck went from moving in a straight path to moving in a curved path. C. The truck began traveling up a slightly sloped surface. D. The truck went from rolling on a rough surface to rolling on a polished surface.

4

A student applied a constant force to a toy truck. A graph of the truck’s movement is shown below. Which of the following could best explain the change in velocity at time X?

A. The truck’s momentum became greater than its inertia. B. The truck went from moving in a straight path to moving in a curved path. C. The truck began traveling up a slightly sloped surface. D. The truck went from rolling on a rough surface to rolling on a polished surface.

•Looking at the graph you can see that the v/t (acceleration) decreased

•The only answer that would decrease this is C. 4

The table shows the results of an experiment with a projectile fired from a spring gun. The results could be most easily interpreted if the data were

A. entered into a spreadsheet.B. put into a database.C. plotted in a histogram.D. plotted as range vs. angle.

5

The table shows the results of an experiment with a projectile fired from a spring gun. The results could be most easily interpreted if the data were A. entered into a spreadsheet.B. put into a database.C. plotted in a histogram.D. plotted as range vs. angle.

0

2

4

6

8

10

12

Histogram- shows comparisons

Database or spreadsheet shows a “bunch of numbers

Plotting a line graph shows trends

5

To create real-time graphs of an object’s displacement versus time and velocity versus time, a student would need to use a

A motion sensor.B low-g accelerometer.C potential difference probe.D force probe.

6

To create real-time graphs of an object’s displacement versus time and velocity versus time, a student would need to use a

A motion sensor.B low-g accelerometer.C potential difference probe.D force probe.

•When you see the words displacent vs. time and velocity vs. time you need to think MOTION

•Potential difference has to do with electricity

•Force probe has to do with weight

6

How much time will it take for a person to walk the length of a football field (100 yards) at a constant speed of 5ft/s ? A. 20 secondsB. 33 secondsC. 60 secondsD. 166 seconds

7

How much time will it take for a person to walk the length of a football field (100 yards) at a constant speed of 5ft/s ?

You will need to change yards into feet so the units are the same. 100 yards = (100 yards x 3ft/yard) = 300 ft. t

dv

v

dt Rearrange and

solve for t

sftt /605

300

7

An object moves away from a motion detector with a constant speed. Which graph best represents the motion of the object?

8

An object moves away from a motion detector with a constant speed. Which graph best represents the motion of the object?

•Remember that velocity (speed) is defined as distance/time

•If the speed is constant that means it stays the same (straight line)

•Graph B (1/1=1, 2/2=1, 3/3=1, etc.)

8

What event will produce the greatest increase in the gravitational force between the two masses?

A. doubling the large mass B. doubling the distance between the masses C. reducing the small mass by half D. reducing the distance between the masses by half

9

What event will produce the greatest increase in the gravitational force between the two masses?

Use the equations for Universal Gravitation. The distance (r) has the greatest impact on the gravitational force

221

r

mGmF

9

A student holds a book at rest in an outstretched hand. The force exerted on the book by the student is equal to the book’s

A. mass. B. weight. C. volume. D. density.

10

A student holds a book at rest in an outstretched hand. The force exerted on the book by the student is equal to the book’s

A. mass. B. weight. C. volume. D. density. Remember that the force of the book on your hand is the force of gravity…..which is also called your weight

gmweightF 10

A student attempts to measure the mass of abrick by measuring the force required toaccelerate it at 1 m/s2 on a level surface. The force required is 2 N, and the student concludes that the brick has a mass of 2 kg. A balance shows that the mass of the brick is really 1.5 kg. The experimental error is most likely due to

A gravity.B work.C friction.D inertia.

11

A student attempts to measure the mass of a brick by measuring the force required to accelerate it at 1 m/s2 on a level surface. The force required is 2 N, and the student concludes that the brick has a mass of 2 kg. A balance shows that the mass of the brick is really 1.5 kg. The experimental error is most likely due to

A gravity.B work.C friction.D inertia.

2N 1m/s2

maF kga

Fm 2

1

2

Remember that friction acts in the opposite direction to the force and would mean the real force would be less than 2N and thus the real mass would be less

11

A 50-kg child on a skateboard experiences a 75-N force as shown. F = 75 N What is the expected acceleration of the child?

A 0.67 m/s2

B 1.50 m/s2

C 6.70 m/s2

D 25.00 m/s2

12

A 50-kg child on a skateboard experiences a 75-N force as shown. F = 75 N What is the expected acceleration of the child?

Recognize that when you see mass (kg) and F (N), that this is probably a F=ma problem

maF a5075

25.150

75s

ma 12

A ball is dropped from rest from a height6.0 meters above the ground. The ball fallsfreely and reaches the ground 1.1 seconds later.What is the average speed of the ball?

A 5.5 m/sB 6.1 m/sC 6.6 m/sD 11 m/s

13

A ball is dropped from rest from a height6.0 meters above the ground. The ball fallsfreely and reaches the ground 1.1 seconds later.What is the average speed of the ball?

01

01

tt

dd

t

dv

smv /5.5

01.1

06

13

A 10-newton force and a 15-newton force areacting from a single point in oppositedirections. What additional force must beadded to produce equilibrium?

A 5 N acting in the same direction as the10-N forceB 5 N acting in the same direction as the15-N forceC 10 N acting in the same direction as the10-N forceD 25 N acting in the same direction as the15-N force

14

A 10-newton force and a 15-newton force areacting from a single point in oppositedirections. What additional force must beadded to produce equilibrium?

15N 10N

5N

5 N acting in the same direction as the10-N force

14

The figure shows a block that is being pulledalong the floor. According to the figure, what isthe acceleration of the block?

A 2 m/s2

B 3 m/s2

C 4 m/s2

D 6 m/s2

15

The figure shows a block that is being pulledalong the floor. According to the figure, what isthe acceleration of the block?

•Start by calculating the net force (50 – 10 = 40N)

•Then use F=ma to calculate the acceleration

maF 2220

40sm

m

Fa

15

A soccer player kicks a 0.5-kilogram stationaryball with a force of 50 newtons. What is theforce on the player’s foot?

A 0 NB 25 NC 50 ND 100 N

16

A soccer player kicks a 0.5-kilogram stationaryball with a force of 50 newtons. What is theforce on the player’s foot?

Remember Newton’s Third Law:

For every action there is an equal and opposing reaction (same force in opposite direction)

50N

50N

16

A student in a lab experiment jumps upward off a common bathroom scale as the lab partner records the scale reading. What does the lab partner observe during the instant the student pushes off?A The scale reading will remain unchangedduring the entire time the student is in contactwith the scale.B The scale reading will increase momentarilythen will decrease as the student is movingupward from the scale.C The scale reading will increase during theentire time the student is in contact with thescale.D The scale reading will decrease momentarilythen will increase as the student is movingupward from the scale.

17

A student in a lab experiment jumps upward off a common bathroom scale as the lab partner records the scale reading. What does the lab partner observe during the instant the student pushes off?B The scale reading will increase momentarily then will decrease as the student is moving upward from the scale.

17

A ball is thrown straight up and then fallsstraight back down. When it attains maximumheight, the ball’s velocity is

A equal to its displacement.B equal to its displacement divided by the time.C at its maximum.D at its minimum.

18

A ball is thrown straight up and then fallsstraight back down. When it attains maximumheight, the ball’s velocity is

At the top of the trajectory the vertical velocity is zero

At its minimum

18

A communication satellite is in a circular orbitaround Earth. If the speed of the satellite isconstant, the force acting on the satellite

A is zero.B is decreasing.C points toward the center of Earth at all times.D points in the direction that the satellite ismoving.

19

A communication satellite is in a circular orbitaround Earth. If the speed of the satellite isconstant, the force acting on the satellite

Remember the the force acting on an object in uniform circular motion is always directed to the center of the circle 19

A satellite that is moving in a circular orbit around Earth and maintaining a constant speed will experience a

A. changing gravitational force toward Earth.B. net gravitational force toward Earth.C. changing acceleration away from Earth.D. net acceleration away from Earth.

20

A satellite that is moving in a circular orbit around Earth and maintaining a constant speed will experience a

As in the previous problem, the force is always directed to the center (net gravitational force toward Earth)

20

The picture shows the circular path of a toyplane being swung around on a string. Whatpath would the toy take if the string broke?

21

A ball on a rope swings around a vertical pole. In which direction will the ball fly if released at the location shown?

A. WB. XC. YD. Z

22

A ball on a rope swings around a vertical pole. In which direction will the ball fly if released at the location shown?

22

A 2.0-kilogram mass is moving with a speed of3.0 m/s. What is the kinetic energy of the mass?

A 1.5 JB 6.0 JC 9.0 JD 12.0 J

23

A 2.0-kilogram mass is moving with a speed of3.0 m/s. What is the kinetic energy of the mass?

•Use the equation to solve for kinetic energy

•Plug in values into equation and solve

2

2

1mvKE 20.30.2

2

1KE

JKE 0.9182

10.90.2

2

1

23

Three objects move with a velocity of 1m/sWhat is the total kinetic energy of the system?

A 1 JB 2 JC 5 JD 10 J 24

Three objects move with a velocity of 1m/s. What is the total kinetic energy of the system?

•Use equation for Kinetic Energy

•To find total KE, add up the total mass (=10kg)

•It already says each object has a velocity of 1 m/s

2

2

1mvKE JKE 5110

2

1 2

24

A 50-kilogram firefighter is on a ladder 10 meters above the ground. When the firefighter descends to 5 meters above the ground, the firefighter’s gravitational potential energy will decrease by

A 0.194 joules. B 5.10 joules. C 490 joules. D 2450 joules.

25

A 50-kilogram firefighter is on a ladder 10 meters above the ground. When the firefighter descends to 5 meters above the ground, the firefighter’s gravitational potential energy will decrease by

You can’t use the equation for KE to solve because they do not give you velocity (v)

Use the relationship between gravitational potential energy and Kinetic energy to solve

•Solve for Potential energy knowing that it will all turn into kinetic energy

mghPE KEJPE 490108.950

25

A hydraulic lift used at an automotive repairshop raises a 1000-kilogram car two meters offof the ground. What is the potential energygiven to the car?

A 1000 JB 2000 JC 9800 JD 19,600 J

26

A hydraulic lift used at an automotive repairshop raises a 1000-kilogram car two meters offof the ground. What is the potential energygiven to the car?

2 meters

1000kg• Use equation for PE

• Use values given and plug into equation

mghPE

JPE 600,1928.91000

26

A high diver steps off a diving platform that is10 meters above the water. If no air resistanceis present, during the fall there will be adecrease in the diver’s

A gravitational potential energy.B total mechanical energy.C kinetic energy.D momentum.

27

A high diver steps off a diving platform that is10 meters above the water. If no air resistanceis present, during the fall there will be adecrease in the diver’s

Decrease in gravitational potential energygravitational potential energy.total mechanical energy.kinetic energy.momentum.

x

A 2.5-kg brick falls to the ground from a3-m-high roof. What is the approximate kineticenergy of the brick just before it touches theground?

A 75 JB 38 JC 12 JD 11 J

x

A 2.5-kg brick falls to the ground from a3-m-high roof. What is the approximate kineticenergy of the brick just before it touches theground?

You can’t use the equation for KE to solve because they do not give you velocity (v)

Use the relationship between gravitational potential energy and Kinetic energy to solve

•Solve for Potential energy knowing that it will all turn into kinetic energy

mghPE KEJPE 7538.95.2

27

A child is on a sled moving down a hill at20 meters/second. The combined mass of the sled and child is 100 kilograms. The momentum of the child and sled is

A 5 kilogram •m/sB 20 kilogram • m/sC 1000 kilogram • m/sD 2000 kilogram • m/s

28

A child is on a sled moving down a hill at20 meters/second. The combined mass of the sled and child is 100 kilograms. The momentum of the child and sled is

•Use the equation for momentum

•Plug in values of mass and velocity

mvp

smkgp /200020100

28

A 70-kg skier leaves a ski jump at a velocity of 14 m/s . What is the skier’s momentum at that instant?

A 5N·sB 50 N·sC 980 N·sD 9800 N·s

29

A 70-kg skier leaves a ski jump at a velocity of 14 m/s . What is the skier’s momentum at that instant?



•Remember that kg·m/.s = N·s

mvp smkgp /9801470

29

When is linear momentum conserved?

A when only nonlinear forces are presentB when more linear than nonlinear forces are inthe systemC when internal forces exceed external forcesD when the net force on the system is zero

30

When is linear momentum conserved?

A. when only nonlinear forces are presentB. when more linear than nonlinear forces are inthe systemC. when internal forces exceed external forcesD. when the net force on the system is zero

30

In collisions between two objects, kinetic energy is conserved only

A. if one of the objects was initially at rest.B. if potential energy converts to work energy.C. in inelastic collisions. D. in elastic collisions.

31

In collisions between two objects, kinetic energy is conserved only

in elastic collisions.

Elastic collisions- all kinetic energy transfered

Inelastic collisions- Some energy transferred to heat energy (kinetic energy lost)

31

What is the momentum of an asteroid that has a mass of 1.35 ×1012 kg and a velocity of 2.55 ×104 m/s?

A 18. 9 ×10 −8 kg·m/s B 52. 9 ×10 7 kg·m/s C 34. 4 ×1016 kg·m/s D 878 ×10 20 kg·m/s

32

What is the momentum of an asteroid that has a mass of 1.35 ×1012 kg and a velocity of 2.55 ×104 m/s?



•You really do not have to do the math…….remember that you add them when you multiply exponents so your answer will be somewhere close to 1016)

mvp kg·m/s 4.341055.21035.1 16412 xxp

32

When these two freight cars of different masscollide and couple, what will be their resultantvelocity?

A 1m/sB 2m/sC 4m/sD 8m/s

33

When these two freight cars of different masscollide and couple, what will be their resultantvelocity?

•Remember that momentum is always conserved!

•Calculate momentum before and that will equal momentum after

mvp 40040 mvpbefore 403010 vmvp afterafter

v4040 smv /133

The diagram depicts a 2-kg mass colliding withand sticking to a second box.

What is the mass of the second box?A 4 kgB 6 kgC 8 kgD 9 kg

34

The diagram depicts a 2-kg mass colliding withand sticking to a second box. What is the mass of the second box?•Remember that momentum is always conserved!

•Calculate momentum before and that will equal momentum after

mvp 606 mvpbefore 401 mmvp afterafter

16 m kgm 61

6

If the total mass is 6kg then the second box is

6 – 2 = 4kg 34

A cup of water at 40 ºC and a cup of water at 5 ºC are left on a table. Which graph correctly shows the temperature of the two cups of water as time passes?

35

A cup of water at 40 ºC and a cup of water at 5 ºC are left on a table. Which graph correctly shows the temperature of the two cups of water as time passes? •The hot water will cool down and the

cold water will heat up until they are mixed totally (equilibrium)

•All water comes to room temperature

35

An engine has an input of heat energy of10,750 J and does 2420 J of work. Which of thefollowing is the heat loss?

A 0.225 JB 4.44 JC 8330 JD 13,170 J

36

An engine has an input of heat energy of10,750 J and does 2420 J of work. Which of thefollowing is the heat loss?

•This is actually a simple question!

•Take the total energy input minus the amount of work done and that equals the heat loss

•Remember that units for energy and work are always Joules (J) and

J83302420750,10

36

The pressure of a gas inside a closed, rigidcontainer will increase when the gastemperature increases. The pressure of the gasincreases because the

A density of the gas decreases.B rate of collisions of gas molecules with thesurface increases.C container expands in size when heated.D gas molecules bond together to form moremassive molecules

37

The pressure of a gas inside a closed, rigidcontainer will increase when the gastemperature increases. The pressure of the gasincreases because the

rate of collisions of gas molecules with thesurface increases.

37

A gas in a sealed cylinder is heated.Which of the following does not increase as the gas is heated?

A the average number of gas molecules hittingthe cylinder walls per secondB the average kinetic energy of the gasmoleculesC the average speed of the gas moleculesD the average distance between the gasmolecules

38

A gas in a sealed cylinder is heated.

Which of the following does not increase as the gas is heated?

•Make sure that you saw the “not increase”

•Molecules move faster when get hotter, thus the kinetic energy increases (KE=1/2mv2)

•Gas molecules are already spread apart evenly…..so

A the average number of gas molecules hittingthe cylinder walls per secondB the average kinetic energy of the gasmoleculesC the average speed of the gas molecules

D the average distance between the gas molecules

38

A heated gas expands, raising a piston. Which of the following describes the energy exchanges of this process?

A. Energy is transferred to the gas by the piston, and to the piston from the heat source. B. Energy is transferred to the gas from the heat source, and to the raised piston from the gas.C. Energy is transferred to the gas in the form of heat and work done by the piston. D. Energy is transferred directly to the piston from the heat source.

39

A heated gas expands, raising a piston. Which of the following describes the energy exchanges of this process?

B. Energy is transferred to the gas from the heat source, and to the raised piston from the gas.

A. Energy is transferred to the gas by the piston, and to the piston from the heat source.

B. Energy is transferred to the gas from the heat

source, and to the raised piston from the gas.

C. Energy is transferred to the gas in the form of heat and work done by the piston.

D. Energy is transferred directly to the piston from the heat source.

39

When a gas is heated in a closed container, theinternal pressure increases. Which bestdescribes the reason for the increase inpressure?

A The average kinetic energy of the gasmolecules decreases.B The potential energy of the gas increases.C The average kinetic energy of the gasmolecules increases.D The potential energy of the gas decreases.

40

When a gas is heated in a closed container, theinternal pressure increases. Which bestdescribes the reason for the increase inpressure?

C. The average kinetic energy of the gasmolecules increases.

40

In which of the following processes is the orderof the system increasing?

A shaking a jar containing separate layers of saltand pepperB smashing a coffee cup with a hammerC adding cold milk to a cup of hot coffeeD forming crystals in a solution

41

In which of the following processes is the orderof the system increasing?A shaking a jar containing separate layers of saltand pepperB smashing a coffee cup with a hammerC adding cold milk to a cup of hot coffee

D forming crystals in a solution

disorder order

If you look at the possible answers, D is the only one that differs from the other three

41

A proposed ideal heat engine would run with a high temperature reservoir at 800 kelvin and a low temperature reservoir at 300 kelvin. When the engine is running, it extracts 400 joules of energy from the hot reservoir and does 250 joules of work each minute. How much energy is expelled to the low temperature reservoir each minute?

A 150 J B 250 J C 300 J D 400 J

42

A proposed ideal heat engine would run with a high temperature reservoir at 800 kelvin and a low temperature reservoir at 300 kelvin. When the engine is running, it extracts 400 joules of energy from the hot reservoir and does 250 joules of work each minute. How much energy is expelled to the low temperature reservoir each minute?

•This is actually a simple question!

•Take the total energy input minus the amount of work done and that equals the heat loss

•Remember that units for energy and work are always Joules (J) and

J150250400

42

Nitrogen molecules within a glass tube are allowed to move randomly. Which figure shows the molecules in a state of greatest entropy?

43

Nitrogen molecules within a glass tube are allowed to move randomly. Which figure shows the molecules in a state of greatest entropy?

•Remember that entropy is a measure of disorder

•The natural tendency of things is to become more disordered!

•Choice C is the most “spread out” or disordered

43

Entropy decreases when

A. wood burns.B. water freezes.C. a snowball melts.D. an iron nail rusts.

44

Entropy decreases when

A. wood burns.B. water freezes.C. a snowball melts.D. an iron nail rusts.

•Remember that entropy is a measure of disorder

•The natural tendency of things is to become more disordered!

•Choice B is the only one where there is more order, or less entropy

44

A container of cold water is dumped into alarger container of hot water. It is mixed andthen left alone for a long time interval. Thewater temperature is found to

A randomly vary from region to region in thecontainer.B be uniform throughout the container.C fluctuate at all positions in the container.D be greater at the bottom of the container.

45

A container of cold water is dumped into alarger container of hot water. It is mixed andthen left alone for a long time interval. Thewater temperature is found to

B. be uniform throughout the container. •When two objects come into contact with each other, heat flows from the hot to the cold object.

•They reach an equilibrium state as molecules collide into each other over time.

45

A radio station transmits to a receivingantenna. The radio wave sent is a

A sound wave.B torsional wave.C longitudinal wave.D transverse wave.

46

A stretched spring attached to two fixed pointsis compressed on one end and released, asshown below. The resulting wave travels back and forth between the two fixed ends of the spring until it comes to a stop. This mechanical wave is an example of a

A transverse wave.B longitudinal wave.C superpositioned wave.D refracted wave.

47

A stretched spring attached to two fixed pointsis compressed on one end and released, asshown below. The resulting wave travels back and forth between the two fixed ends of the spring until it comes to a stop. This mechanical wave is an example of a B. longitudinal wave.

•It is either going to be a longitudinal or transverse wave

•Sound waves are also longitudinal waves

47

A sound wave traveling through a solidmaterial has a frequency of 500 hertz. Thewavelength of the sound wave is 2 meters. Whatis the speed of sound in the material?

A 250m/sB 500m/sC 1000m/sD 250,000m/s

48

A sound wave traveling through a solidmaterial has a frequency of 500 hertz. Thewavelength of the sound wave is 2 meters. Whatis the speed of sound in the material?

•Use equation for waves v = λf

•v = velocity (in m/s)

•λ = wavelength , and f = frequency

•Plug in values and solve

fv smv /10005002 48

A sound wave is produced in a metal cylinder by striking one end. Which of the following occurs as the wave travels along the cylinder?

A. Its amplitude increases.B. Its frequency increases.C. It transfers matter.D. It transfers energy.

49

A student shakes the end of a rope with a frequency of 1.5 Hz, causing waves with a wavelength of 0.8 m to travel along the rope. What is the velocity of the waves? A 1.9 m/sB 1.6 m/sC 1.2 m/sD 0.53 m/s

50

A student shakes the end of a rope with a frequency of 1.5 Hz, causing waves with a wavelength of 0.8 m to travel along the rope. What is the velocity of the waves?

•Use equation for waves v = λf

•v = velocity (in m/s)



fv smv /2.15.18.0 50

A tuning fork is used to produce sound waveswith a frequency of 440 hertz. The waves travelthrough the air at 344m/s. What is the wavelength of the sound waves?

A 0.15 mB 0.39 mC 0.78 mD 1.28 m

51

A tuning fork is used to produce sound waveswith a frequency of 440 hertz. The waves travelthrough the air at 344m/s. What is the wavelength of the sound waves?

•Use equation for waves v = λf and solve for λ•v = velocity (in m/s)



f

v m78.0

440

344

51

Astronauts on the Moon would not be able tohear a landslide because

A the lunar dust deadens sounds.B intensive sunlight destroys sound waves.C the magnetic field of the Moon is too weak tocarry sound.D air molecules on the Moon are too far apart tocarry sound.

52

Astronauts on the Moon would not be able tohear a landslide becauseD. air molecules on the Moon are too far apart tocarry sound. •The key is to remember that sound waves need a medium to transfer the energy.

•On the moon the atmosphere is too thin and there is nothing (no molecules) to transfer the energy

52

The graph below depicts the relationship between wave energy and wave amplitude.

How is the energy of the wave affected if the amplitude of the wave increases from 2 meters to 4 meters? A It is halved.B It is doubled.C It is quadrupled.D It remains the same.

53

Objects appear different in size and shape in acontainer of water due to

A refraction of the light waves.B interference of the water and light waves.C polarization of the light waves.D diffraction of the light waves.

54

What is the wavelength of a 264-Hz sound wave when the speed of sound is 345m/s ?

A. 0.77 mB. 1.31 mC. 6.09 mD. 9.11 m

55

What is the wavelength of a 264-Hz sound wave when the speed of sound is 345 m/s ?

•Use equation for waves v = λf and solve for λ•v = velocity (in m/s)



f

v m31.1

264

345

55

Sound waves cannot carry energy through

A water.B air.C a mirror.D a vacuum.

56

Sound waves cannot carry energy through

A. water.B. air.C. a mirror.D. a vacuum.

56

Where does visible light fall on the electromagnetic spectrum?

A. between x-rays and gamma rays B. between short-wave radio and television C. between infrared and ultraviolet D. between microwaves and infrared

57

Where does visible light fall on the electromagnetic spectrum?

•Between infrared and ultraviolet

•ROYGBIV

57

An engineer in a moving train blows the train’shorn. The train is moving away from a personstanding on the ground. Compared to thefrequency of the sound that the engineer hears,the person standing on the ground hears asound with

A the same wavelength.B more variation in tone.C greater amplitude.D a lower frequency.

58

An engineer in a moving train blows the train’shorn. The train is moving away from a personstanding on the ground. Compared to thefrequency of the sound that the engineer hears,the person standing on the ground hears asound with

•This is known as the Doppler Effect

•Since we know the relationship v = λ·f, since λ remains constant, sound waves get to your ear slower (less velocity), so the frequency is lower

Higher frequency Lower frequency

58

In this circuit, what is the current through the2-ohm resistor?

A. 0.2 AB. 0.8 AC. 5.0 AD. 8.0 A

59

In this circuit, what is the current through the2-ohm resistor?

•This is a simple question using Ohm’s law

•You must understand that the Voltage through each branch is the same in a parallel circuit (10V)

AA R

VI

•IA is current in branch A and RA is resistance in branch A

•You need to remember the units

•Current = Amps (A)

•Resistance = Ohms (Ω)

•Voltage = Volts (V)

AI A 52

10

59

How many amperes of current will flow whenfour 1-ohm resistors are in this series circuit?

A 0.5 ampereB 1.0 ampereC 1.5 amperesD 2.0 amperes

60

How many amperes of current will flow whenfour 1-ohm resistors are in this series circuit?

•All you need to remember is to use Ohm’s law equation

R

VI

•In a series circuit you just add up the total resistance (1+1+1+1=4Ω)

•Plug in values and solve for I (current)

AI 5.14

6

60

In the circuit shown above, the meter registers1.5 amperes. The voltage across the 10.0-ohmresistor is about

A 1.5 V.B 6.7 V.C 8.5 V.D 15.0 V.

61

In the circuit shown above, the meter registers 1.5 amperes. The voltage across the 10.0-ohmresistor is about

•Recognize this is also a problem you need to use Ohm’s law to solve (has voltage, resistance & current)

•Rearrange and solve for V

•Also recognize this as a series circuit (makes it simple)

R

VI IRV VV 150.105.1

61

What is the current through the battery?

A. 1 AB. 2 AC. 4 AD. 8 A

62

What is the current through the battery?

• This is another Ohm’s law problem

• Remember to get total resistance you simply add up the resistance

• Plug in values and solve

R

VI AI 1

8

8

62

A 9-V battery is connected to a light bulb with a resistance of 3 Ω. What is the current in the circuit?

A. 27 AB. 3.0 AC. 1.0 AD. 0.3 A

63

A 9-V battery is connected to a light bulb with a resistance of 3 Ω. What is the current in the circuit?

•Another Ohm’s law problem

•This is a simple series circuit

R

VI

AI 33

9

63

An electric appliance draws 1.5 amperes of current when it is connected to a 24-volt source. What is the resistance of this appliance?

A. 0.063 ohmB. 11 ohmsC. 16 ohmsD. 54 ohms

64

An electric appliance draws 1.5 amperes of current when it is connected to a 24-volt source. What is the resistance of this appliance?

•Use Ohm’s Law to solve

•Rearrange and solve for R (resistance)

R

VI

I

VR

ohmsR 165.1

24

64

How much power is dissipated by the resistor in the circuit above?

A. 25 watts B. 50 watts C. 100 watts D. 800 watts

65

How much power is dissipated by the resistor in the circuit above?

•When asked to calculate power, use P = I·V

•At this point you will first have to solve for I (current) using Ohm’s Law


IVP wattsP 501005.0

AR

VI 5.0

200

100

65

A transistor circuit is used as an amplifier.When a signal is applied to the input of thetransistor, the output signal is

A a smaller amplitude.B an equal amplitude.C a larger amplitude.D zero amplitude.

66

A transistor circuit is used as an amplifier.When a signal is applied to the input of thetransistor, the output signal is

A a smaller amplitude.B an equal amplitude.C a larger amplitude.D zero amplitude. •Just know that transistors increase the amplitude of the output signal

66

A metal bar magnet has a magnetic field in theregion of space around it. The magnetic field isdue to

A magnetic monopoles embedded in the metal.B a hidden voltage source in the metal.C the motion of charged particles in the metal.D an electric current that runs along the lengthof the magnet.

67

A metal bar magnet has a magnetic field in theregion of space around it. The magnetic field isdue to

C the motion of charged particles in the metal.

67

Two oppositely charged particles are held in place near each other. When the particles are released, they will most likely

A. accelerate away from each other.B. accelerate toward each other.C. rotate in a clockwise direction.D. rotate in a counterclockwise direction.

68

Two oppositely charged particles are held in place near each other. When the particles are released, they will most likely

B. accelerate toward each other•A very important concept concerning charge is the fact that LIKE CHARGES REPEL AND UNLIKE CHARGES ATTRACT!

68

A coil with a current is shown above. In thecenter of the coil, a magnetic field points

A to the right.B to the left.C upward.D downward.

69

A coil with a current is shown above. In thecenter of the coil, a magnetic field points

•Use the right-hand rule to determine direction of magnetic field

Points to left

69

In order to turn neon gas into neon plasma,

A energy must be removed from the neon gas.B energy must be supplied to the neon gas.C the neon gas must be ignited with a flame.D the neon gas must become a superconductor.

70

In order to turn neon gas into neon plasma,B energy must be supplied to the neon gas.

70

The diagram below shows current flow through a wire.

Which of the following represents the magnetic field resulting from the current?

71

The diagram below shows current flow through a wire. Which of the following represents the magnetic field resulting from the current?

•Use the right hand rule to determine the direction

71

Extremely high temperatures are needed for fusion reactors to function efficiently. What state of matter is most common at these temperatures?

A. plasmaB. gasC. liquidD. solid

72

Extremely high temperatures are needed for fusion reactors to function efficiently. What state of matter is most common at these temperatures?

72

Preparing for tests Know when the test is! Make sure you leave time to study 24 hours before test–...

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