TAKS Physics

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TAKS PhysicsWhat do you know?

Main Topics

• Speed = distance / time• Acceleration = velocity change / time• Newton’s laws (F = ma)• Momentum (p = mv)• Energy (conservation)• Work and power and simple machines• Density = mass / volume• Circuits and electricity• Waves light and sound• Heat transfer

Speed = distance / time

• You might have to solve for any of these three parts.

4A IPCC 10-03

The diagram represents the total travel of a teacher on a Saturday. Which part of the trip is made at the greatest average speed?

A QB RC SD T

4A IPCD 10-03

A car traveled 150 km in 2.5 hours. What

was its average speed in km per hour?

A 37.5 km/h

B 450 km/h

C 75 km/h

D 60 km/h

4A IPCD 11/05The speed of sound in human tissue is

about 1600 m/s. If an ultrasound

pulse takes 1.5 x 10-5s to travel

through a tissue, what is the thickness

of the tissue?

A 2.4 km

B 2.4 m

C 23 cm

D 24 mm

4A IPCD 11/06

A cyclist moves at a constant speed of 5 m/s.

If the cyclist does not accelerate during the

next 20 seconds, he will travel ---

C 50 m

D 100m

4A IPCB 10/06

A driver traveled 270 km in 3 hours. The driver’s destination was still 150 km away. What was the driver’s average speed at this point?

A 40 km/h

B 90 km/h

C 140 km/h

D 420 km/h

4B IPCGB 10/06

Which graph can represent an object at rest?

Acceleration = velocity change / time

• Again, you may have to solve for any of these quantities.

• Acceleration is measured in units of meters per second squared

•m/s2

4A IPCA 11/04

According to this graph, what was the bicycle’s

acceleration between 6 and 10 seconds?

A 0.0 m/s2

B 0.65 m/s2

C 1.6 m/s2

D 6.5 m/s2

4A IPCC 11/06

The table above shows experimental data collected when four cars moved along a straight-line path. According to these data, which car moved with a constant acceleration of 2 m/s2?

A Car QB Car RC Car SD Car T

Newton’s laws (F = ma)

• 1st Law - objects resist accelerationobjects resist acceleration

• An object at rest tends to remain at rest An object at rest tends to remain at rest and an object in motion tends to remain in and an object in motion tends to remain in motion at the same speed and in the same motion at the same speed and in the same direction unless it is acted upon by an direction unless it is acted upon by an unbalanced force.unbalanced force.

• 22ndnd Law – F = ma Law – F = ma

• force is equal to mass times accelerationforce is equal to mass times acceleration

• weight is equal to mass times gravitational weight is equal to mass times gravitational accelerationacceleration

• gravitional acceleration (g) = 9.8 m/sgravitional acceleration (g) = 9.8 m/s2

• 33rdrd Law – for every action there is an equal Law – for every action there is an equal and opposite reactionand opposite reaction

• only two forces and only two objectsonly two forces and only two objects

• If object A applies a force on object B, If object A applies a force on object B, then object B then object B MUSTMUST apply the same size apply the same size force on object A in the opposite direction.force on object A in the opposite direction.

4B IPCD 11/06A hockey player pushed a puck toward the

opposite side of a level ice rink. The player expected the puck to continue all the way across the ice, but the puck slowed and stopped before reaching the other side. Which of these best explains why the puck failed to slide all the way to the opposite side?

A The puck’s temperature changed.

B An upward force acted on the puck.

C The puck’s momentum remained

unchanged.

D An opposing force acted on the puck.

4B IPCD 11/04

Which factor would most likely cause a communications satellite orbiting Earth to return to Earth from its orbit?

A An increase in the satellite’s forward

momentum

B An increase in solar energy striking the

satellite

C A decrease in the satellite’s size

D A decrease in the satellite’s velocity

4B IPCC

The frog leaps from its resting position at the lake’s bank onto a lily pad. If the frog has a mass of 0.5 kg and the acceleration of the leap is 3 m/s2, what is the force the frog exerts on the lake’s bank when leaping?

A 0.2 NB 0.8 NC 1.5 ND 6.0 N

4A IPCB 10-03

How much force is needed to accelerate

a 1,300 kg car at a rate of 1.5 m/s2?

A 867 N

B 1,950 N

C 8,493 N

D 16,562 N

4A IPCD 11/05

A 16 NB 32 NC 88 ND 100 N

Starting from rest at the center of a skating rink, two skaters push off from each other over a time period of 1.2 s. What is the force of the push by the smaller skater?

4A IPCJD 11/06

What is the net force exerted on a 90.0 kg

race-car driver while the race car is

accelerating from 0 to 44.7 m/s in 4.50 s?

A 9.8 N

B 20 N

C 201 N

D 894 N

4B IPCB 490N 11/04

How many newtons of force does a 50.0 kg deer exert on the ground because of gravity?

A 49.0NB 490NC 59.8ND 1470N

4B IPCC 11/04Which of these is the best description of the

action-reaction force pair when the space shuttle lifts off from the launchpad?

A The ground pushes the rocket up while exhaust gases push down on the ground.B Exhaust gases push down on air while the air pushes up on the rocket.C The rocket pushes exhaust gases down while the exhaust gases push the rocket up.D Gravity pulls the rocket exhaust down while friction pushes up against the atmosphere.

4B IPCD 11/05

The picture above shows the direction in which water leaves the scallop’s shell. Which picture below shows the direction the scallop will move?

4B IPCGB 11/06When the air is released from a balloon, the air

moves in one direction, and the balloon moves in another direction. Which statement does this situation best illustrate?

A What goes up must come down.

B For every action, there is an equal and

opposite reaction.

C The shape and size of an object affect air

resistance.

D The acceleration due to Earth’s gravity is

9.8 m/s2.

4B IPC

D 10-04

The illustration above shows a student about to throw a ball while standing on a skateboard. Which illustration below correctly shows the skateboard’s direction of motion after the student releases the ball?

Momentum (p = mv)

• You may be asked to solve for any of these quantities.

• Momentum MUST be conserved. (Along with mass and energy)

• The unit is the kilogram meter per second

•kg m/s

4A IPCJD 11/05

The table contains data for two wrecking balls being used to demolish a building. What is the difference in momentum between the two wrecking balls?

A 300 kgm/s

B 200 kgm/s

C 150 kgm/s

D 0 kgm/s

4A IPCD 11/05

A 0.50 kg ball with a speed of 4.0 m/s strikes a stationary 1.0 kg target. If momentum is conserved, what is the total momentum of the ball and target after the collision?

A 0.0 kgm/s

B 0.5 kgm/s

C 1.0 kgm/s

D 2.0 kgm/s

4A IPCHC 11/06

The 500 g cart is moving in a straight line at a constant speed of 2 m/s. Which of the following must to 250 g toy car have in order to maintain the same momentum as the cart?

A An acceleration of 5 m/s2 for 2 secondsB A potential energy of 20 JC A constant velocity of 4 m/sD An applied force of 5 N for 5 seconds

4A IPCA 10/04

Which bike rider has the greatest momentum?

A A 40 kg person riding at 45 km/h

B A 50 kg person riding at 35 km/h

C A 60 kg person riding at 25 km/h

D A 70 kg person riding at 15 km/h

4A IPCD

A ball moving at 30 m/s has a

momentum of 15 kg.m/s. The

mass of the ball is ___

A 45 kg

B 15 kg

C 2.0 kg

D 0.5 kg

4B IPC630 11/06

The pictures show how an air bag functions in a collision. How much momentum in kg m/s does the air bag absorb from the crash-test dummy if all the crash-test dummy’s momentum is absorbed by the air bag?

Car velocity = 6.3 m/sDriver velocity = 6.3 m/sDriver mass = 100 kg

Car velocity = 0 m/sDriver velocity = 6.3 m/sDriver mass = 100 kg

Car velocity = 0 m/sDriver velocity = m/sDriver mass = 100 kg

Energy (conservation)

• Energy must be conserved

• Kinetic energy = one half mass times velocity squared

• KE = ½ m x v2

• Gravitational potential energy = mass times gravitational acceleration times height

• PE = mgh

Energy (conservation)

• Energy MUST be conserved.

• (Along with mass and momentum.)

4A IPCB 11/06

A 1-kilogram ball has a kinetic energy of 50 joules. The velocity of the ball is ---

A 5 m/s

B 10 m/s

C 25 m/s

D 50 m/s

6A IPCC

What is the potential energy of the rock?

A. 59,000 joulesB. 64,600 joulesC. 93,100 joulesD. 121,600 joules

6A IPCB 11/06

What is the approximate difference in gravitational potential energy of the two shaded boxes?

A. 19JB. 39JC. 59JD. 79J

6A IPCA 11/04Effect Amount of Energy per

Second (terajoules)

Solar radiation reaching Earth 173,410

Radiation reflected back into space

52,000

Radiation heating atmosphere, landmasses, and oceans

81,000

Radiation producing winds and ocean currents

Radiation used in photosynthesis

Radiation resulting in evaporation of water

Solar Radiation and Earth

Assuming the chart contains all energy transformations in the Earth system, how much solar radiation goes toward evaporating water?

A. 40,000 terajoulesB. 92,410 terajoulesC. 121,410 terajoulesD. 133,410 terajoules

6A IPCA 11/04

Why is the sum of the product’s energy in this reaction less than the sum of the reactants’ energy?

A. Energy is given off as heat.B. The products absorb available energy.C. Energy is trapped in the reactants.D. The reactants’ energy is less than the

melting point of glucose.

C6H12O6 + 6O2 6CO2 + 6H2O

Glucose Water Carbon Water Dioxide3000 kJ 300 kJ 200 kJ 150 kJ

Work and power and simple machines

• Work = force times distance

• W = F x d

• Power = work divided by time

• P = W / t

• Work has NO time factor.

• If the same force is applied over the same distance, the same work is done even if it is done faster in one case.

• If work is done faster, more power is used. Power is how fast work is done.

• Two basic types of machines:

• Lever type simple machines

• (levers, wheel and axles, pulleys) and

• Inclined plane type simple machines

• (inclined planes, wedges, and screws)

• Simple machines may change direction of motion. (Like a pulley)

• A machine may also trade distance for force OR trade force for distance. (A machine CANNOT do both.)

• A machine CANNOT increase the WORK done.

• A simple machine increases output force over a shorter distance by requiring the force you put in to be applied over a longer distance. (You trade distance for force.)

• The mechanical advantage of a machine is force output divided by force input.

• It is greater than 1 if the machine puts out more force than you put in.

• It is less than 1 if the machine puts out less force than you put in.

4A IPCA 10-04

How much work is performed when a 50 kg crate is pushed 15 m with a force of 20N?

A 300 JB 750 JC 1,000 JD 15,000 J

4A IPCB

If a force of 100 newtons was exerted on

an object and no work was done, the

object must have ---

A accelerated rapidly

B remained motionless

C decreased it velocity

D gained momentum

4A IPCC 11/04

A mechanic used a hydraulic lift to raise

a 12,054 N car 1.89 m above the floor of

a garage. It took 4.75 s to raise the car.

What was the power output of the lift?

A 489 W

B 1815 W

C 4796 W

D 30,294 W

4A IPCC 11/05

A horizontal force of 600 N is used to push a

box 8 m across a room. Which of these

variables must be known to determine the

power used in moving the box?

A The weight of the box

B The potential energy of the box

C The time it takes to move the box

D The length of the box

4A IPCc 11/06

A woman lifts a 57-newton weight a distance

of 40 centimeters each time she does a

particular exercise. It takes her 0.60 second

to lift the weight. How much power does she

supply for lifting the weight one time?

A 24 W

B 34 W

C 38 W

D 95 W

4A IPCHC 11/06

An advertisement claims that a certain truck

has the most powerful engine in its class. If

the engine has more power, which of the

following can the truck’s engine do,

compared to every other engine in its class?

A Produce fewer emissions

B Operate more efficiently

C Perform work faster

D accelerate longer

4A IPCB 10/06A person pushes a large box across a level

floor by applying a horizontal force of 200 N. If the person pushes the box a distance of 5 meters in 10 seconds, how much work does the person do on the box?

A 2000 joules

B 1000 joules

C 400 joules

D 100 joules

4A IPCHC 11/04

The weight lifter used a force of 980 N to raise the barbell over her head in 5.21 seconds. Approximately how much work did she do in raising the barbell?

A 380 L

B 982 J

C 2,000 J

D 10,000 J

4D IPCFA11/04

Which lever arrangement requires the least effort to raise a 500 N resistance?

4D IPCHC11/06

Which configuration of pulleys and belts shown below will result in the fastest rotation of spindle 2?

4D IPCC11/06

Which of these represents a properly balanced system?

4D IPCGB

The diagram shows an electric motor lifting a 6 N block a distance of 3 m. The total amount of electrical energy used by the motor is 30 J. How much energy does the motor convert to heat?

A 9 JB 12 JC 18 JD 21 J

Efficiency

• Efficiency is calculated by dividing work output by work input and multiplying it by 100%.

• The efficiency can NEVER be more than 100%.

4D IPCGB11/04

What is the efficiency of an air conditioner if there is a work input of 320 J and a work output of 80 J?

C 240%

D 400%

Density = mass / volume

• Be able to solve for any of the three values.

• The unit is grams per milliliter or

• grams per cubic centimeter

• g/ml or g/cm3

Circuits and electricity

• Voltage = current x resistance

• V = IR

• Power = current x voltage

• P = IV

6F IPCA 10-04

How much current is flowing through this circuit?

A 0.32 AB 3.1 AC 4.0 AD 12.5 A

6F IPCA 10/06

In this circuit, how much current flows through the lightbulb?

A. 0.75 ampB. 1.50 ampsC. 2.0 ampsD. 3.0 amps

6F IPCC 10/06

The bulb will light when a current supplied by at least one 1.5 V battery is available. Which current will fail to light the bulb?

6F IPC A 10-03

Which switch, if opened, will cause the lightbulb to stop glowing?

A. QB. RC. SD. T

6F IPCG 10-03

What is the current in a copper wire that has a resistance of 2 ohms and is connected to a 9-volt electrical source?

A. 0.22 ampB. 4.5 ampsC. 11.0 ampsD. 18.0 amps

6F IPCJD10-04

Which circuit is built so that if one lightbulb goes out, the other three lightbulbs will continue to glow?

Waves light and sound

• Velocity = frequency x wavelength

• v = f x

• Two types of waves: compression and transverse waves

• Sound is a compression (longitudinal) wave

• Light is a transverse wave.

Properties of Waves

• Interference - waves cross over each other

• can increase or decrease amplitude

Properties of Waves

• Resonance - the vibration of one object causes the vibration of another object without contact

Properties of Waves

• Reflection - a wave ounces off a boundary

• The angle of reflection is equal to the angle at which the wave meets the boundary.

Properties of Waves

• Refraction - the bending of a wave as it changes speed moving from one medium to another

Properties of Waves

•Diffraction - the bending of a wave as it moves around an obstruction or through an opening

Properties of Waves

• Polarization - allowing only one orientation of a transverse wave to pass

• Only transverse waves can be polarized.

5A IPCB 10-04

Which illustration best demonstrates compression waves?

5B IPCC

One tuning fork is struck and placed next to an identical fork. The two forks do not touch. The second tuning fork starts to vibrate because of ---

A. interferenceB. the Doppler effectC. resonanceD. standing waves

5A IPCA 10/06

Which label on the model represents a wavelength?

5B IPCC11/06An empty cup was tightly covered with plastic

wrap, and a few grains of salt were sprinkled on top of the plastic. When a tuning fork was struck and placed slightly above the plastic wrap, the salt began to move. Which characteristic of waves does the movement of the salt best demonstrate?

A. Echo formationB. DiffractionC. ResonanceD. Specular reflection

5B IPCD11/06

When a DVD is read, laser light touches the DVD surface and is then measured at location A. What allows light to return to location A after striking the DVD surface?

A. ConductionB. RefractionC. MagnificationD. Reflection

Laser Light Striking a DVD

5B IPCA11/04

The pitch of a sound made by plucking a guitar string is determined by the ---

A. frequency of the vibration producedB. strength of the plucking forceC. distance between the stringsD. shape of the guitar body

5B IPCA11/05A tuning fork with a frequency of 256 Hz

vibrates when struck. Because of these vibrations, a nearby tuning fork begins to vibrate without being struck. Which of the following best accounts for the vibrations of the second tuning fork?

A. ResonanceB. PolarizationC. DiffractionD. Refraction

5B IPCB11/06

A guitar player is seated next to a piano. The piano player strikes an E key on the piano. The guitarist reports that this causes the E string on his guitar to vibrate. What is the name of this phenomenon?

A. PolarizationB. ResonanceC. ReflectionD. Diffraction

5B IPCB11/04

A. ReflectionB. RefractionC. DiffractionD. Polarization

When trying to spear a fish in water, a person needs to take into account the way light bends as it moves from water into the air. The bending of light as it passes from one medium into another is known as ---

5B IPCF11/05

A surface wave generated by an earthquake was recorded at Seismic Station 1. Forty seconds later the same wave was recorded at Seismic Station 2. What accounts for the time difference?

A.The origin of the wave is closer to Seismic Station 1.B.The speed of the wave decreases with distance.C.The wavelength is longer at Seismic Station 2.D.The wave frequency increases when the wave

passes through soil.

5B IPCB11/04

Which wave has the greatest velocity?

5B IPCD11/04

Which wave has the least velocity?

5B IPCD 11/06

A. DiffusionB. ReflectionC. DiffractionD. Refraction

Diverging lenses are useful to people who suffer from nearsightedness because the lenses can cause images of distant objects to be focused on the retina. Lenses allow images to be focused on the retina because of ---

5B IPCB 11/05

The diagram shows waves approaching a barrier. Which pattern will be formed after the waves pass through the opening in the barrier?

Heat Transfer

• Conduction - transfer from one particle to another with contact

• Convection - transfer of heat containing particles in a fluid due to differences in density

• Radiation - transfer from one particle to another without the need for contact

6B IPCB

Heat convection occurs in gases and liquids. Heat convection does not occur in solids because solids are unable to ---

A. absorb heat by vibratingB. transfer heat by fluid motionC. emit radiation by reflecting lightD. exchange heat by direct contact

6B IPCB 11/06

The transfer of heat by the movement of air currents in Earth’s atmosphere is an example of ---

A. ConductionB. ConvectionC. RadiationD. Fusion

6B IPCA 10/04

A man who was sleeping wakes up because he hears the smoke alarm go off in his house. Before opening the bedroom door, the man feels the door to see whether it is warm. He is assuming that heat would be transferred through the door by ---

A. ConductionB. ConvectionC. RadiationD. Compression

6B IPCC 10/06

In winter the air just above the top bunk of a bunk bed is warmer than the air just above the bottom bunk because warm air rises. Which of the following describes the method of heating that causes this difference in temperature?

A. Radiation from the roomB. Heat transfer through wallsC.Convection currents in the roomD.Heat conduction through the bed

6B IPCA 10/06

Which of these is the best example of heat transfer by radiation?

A. A satellite is warmed by sunlight.

B. Butter melts on warm bread.

C. A ceiling fan cools a warm room.

D. Puddles of water cool a warm tile floor.

6B IPCD 10/04

Container P and Container Q each were filled with 0.5 liter of water. The water was heated to 90oC. The table shows the temperatures after both containers were allowed to cool for 3 minutes. Compared to Container Q, Container P is a better ---

A. conductorB. absorberC. radiatorD. insulator

Final Temperature

Initial Temperature

(oC)Container

Temperatures of Water inDifferent Containers

6B IPCD 11/04

In which container is the substance unable to transfer heat by convection?

6B IPCJ 10-03

The primary way liquids and gases transmit heat is by the process of ---

A. reflectionB. convectionC. radiationD. convection

6B IPCC

A solar heater uses energy from the sun to heat water. The heater’s panel is painted black to ---

A. Improve emission of infrared radiation

B. Reduce the heat loss by convection currents

C. Improve absorption of infrared radiation

D. Reduce the heater’s conducting properties

TAKS Physics

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