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Scalar quantity indicating the capacity for doing work

A. Power

B. Buoyancy

C. Energy

D. Pressure

Work

A. F/d

B. F//d

C. P/t

D. rV

Total work done equals...

A. Change of momentum

B. Mechanical Advantage

C. Change of Kinetic Energy

D. Change of Power

Joules per second

A. Watt

B. Pascal

C. Newton

D. Kelvin

Work

A. A force applied through a distance

B. Energy of motion

C. The rate at which energy is used

D. Measured in Watts

A horizontal force of 50 N pushes a 3.5 kg box 2.0 meters down the hallway. The work

done is:A. 7.0 J

B. 100 J

C. 17.5 J

D. 70 J

Work done by a force acting perpendicular to the displacement of an object

A. Depends on the distance

B. Depends on the size of the force

C. Depends on the acceleration

D. Zero

Which of the following is not measured in Joules?

A. Heat

B. Spring Potential energy

C. Power

D. Kinetic Energy

Kinetic energy

A. ½ mv2

B. mv2/r

C. mv

D. mgh

Gravitational potential energy

A. ½ kx2

B. mgh

C. Gm1m2/r2

D. m/V

What is the kinetic energy of a 6.0 kg mass that is moving at 2.0 m/s?

A. 12 J

B. 3.0 J

C. 24 J

D. 36 J

What is the gravitational potential energy of a 5.0 kg block that is 6.0 meters above the

ground?A. 300 J

B. 150 J

C. 30 J

D. 3.0 J

The rate at which work is done

A. Kinetic energy

B. Pressure

C. Power

D. Acceleration

A motor lifts a 2.0 kg mass 4.0 meters in 8 seconds. The power output is:

A. 64 W

B. 32 W

C. 40 W

D. 10 W

The work done by a 20 W motor in 4 seconds is

A. 320 J

B. 24 J

C. 5 J

D. 80 J

A falling object has a gravitational potential energy of 240 J and a kinetic energy of 16 J. 1.0 second

later the potential energy is 60 J. What is the kinetic energy? (ignore air resistance) A. 224 J

B. 216 J

C. 180 J

D. 196 J

Conservation of energy

A. Using as little energy as possible

B. Discovering new energy reserves

C. Total amount of energy doesn’t change

D. Total energy decreases over time

Fraction of energy input that is converted into useful work by a machine

A. Mechanical advantage

B. Ideal mechanical advantage

C. Efficiency

D. Power

Ratio of the output force to the input force.

A. Efficiency

B. Ideal Mechanical Advantage

C. Mechanical Advantage

D. Net force

A simple machine can NOT

A. Reduce the amount of energy required to complete a task

B. Reduce the amount of force required to complete a task.

C. Change the direction of a force needed to complete a task

D. A simple machine can do all of those things

Product of power and time

A. Work

B. Momentum

C. Displacement

D. Impulse

The kinetic energy of an 8 kg object is 16 J. How fast is it moving?

A. 4 m/s

B. 2 m/s

C. 1 m/s

D. 8 m/s

A 10.0 kg ball dropped from 15 meters has 1.5 kJ of potential energy. Just before it hits it has a KE

of ____ and a speed of _____:

A. 1.5 kJ, 20 m/s

B. 1.5 kJ, 400 m/s

C. 3.0 kJ, 20 m/s

D. 0.0 kJ, 400 m/s

A person carries a 3.0 kg back pack 40 meters down the hallway. The work done is:

A. 120 J

B. 1.2 kJ

C. 0.75 J

D. Zero

A person drops a 6.0 kg rock from a 10.0 m cliff. When it has fallen half way its total

energy is:A. 600 J

B. 300 J

C. 150 J

D. Equal to its kinetic energy

A 50 kg skier swooshes down a hill that is 40 meters high. At the bottom of the hill his

kinetic energy is:A. 20 kJ

B. 40 kJ

C. 2 kJ

D. 4 kJ

An object moving at 5.0 m/s has 50 J of kinetic energy. Its mass is:

A. 45 kg

B. 2.0 kg

C. 4.0 kg

D. 250 kg

The motor in the previous problem did 125 J of work in 5.0 seconds. If the electrical energy

consumed is 200 J then the motor has an efficiency of:

A. 75%

B. 140%

C. 62.5%

D. 27.5%

Measure of the average kinetic energy of a particle in a system

A. Thermal energy

B. Temperature

C. Heat

D. Entropy

Flow of thermal energy from one object to another

A. Work

B. Temperature

C. Potential Energy

D. Heat

Measure of “disorder” in a system.

A. Energy

B. Enthalpy

C. Entropy

D. Chaos-ergy

Which of the following is NOT forbidden by the second law of thermodynamics?

A. Heat flows spontaneously from cold to hot

B. Entropy increases over time

C. Heat is converted to work with 100% efficiency.

D. Things spontaneously become more ordered.

One Newton per meter squared

A. Farad

B. Joule

C. Pascal

D. Calorie

Total kinetic and potential energy associated with the random motion of particles at the

atomic scale.A. Temperature

B. Thermal Energy

C. Entropy

D. Enthalpy

The temperature at which no thermal energy remains.A. 0o C

B. 0o F

C. 0 K

D. -273 K

The amount of heat needed to raise 1.0 kg of a substance by 1 oCA. Heat of Fusion

B. Heat of Vaporization

C. Coefficient of Thermal Expansion

D. Specific Heat

Transfer of heat by electromagnetic waves.

A. Conduction

B. Radiation

C. Equilibrium

D. Convection

What pressure is exerted by a 20 N force acting on a surface with an area of 4.0 m2?

A. 5.0 Pa

B. 80 Pa

C. 320 Pa

D. 8.0 Pa

A block of metal has a density of 6.0 g/cm3. If its volume is 18 cm3, what is its mass?

A. 3.0 g

B. 0.33 g

C. 10.8 g

D. 0.108 kg

Thermal equilibrium is reached when two systems

A. Have the same thermal energy

B. Have the same specific heat

C. Have the same temperature

D. Have the same entropy

A heat engine uses 12 kJ of thermal energy and does 4.0 kJ of work during each cycle. The engine produces ______ of waste heat each cycle.

A. 3.0 kJ

B. 16 kJ

C. 8.0 kJ

D. 48 kJ

A 250 Pa of pressure are exerted on a surface with an area of 0.5 m2. What is

the amount of force being exerted?A. 125 N

B. 250 N

C. 500 N

D. 1000 N

In a hydraulic system

A. Each piston experiences the same amount of force.

B. Each piston experiences the same amount of pressure

C. The work out can be larger than the work in.

D. The power out can be larger than the power in.

Adding heat to water already at 100o C

A. Increases the temperature more

B. Starts to convert the liquid to a gas but does not raise the temperature.

C. Does not change the thermal energy of the H2O molecules.

D. Will result in overcooked spaghetti nodles.

A heat engine uses 12 kJ of thermal energy and does 4.0 kJ of work during each cycle. The engine

has an efficiency of

A. 33%

B. 300%

C. 67%

D. 16%

A cylinder of gas absorbs 24.0 J of heat and does 8.0 J of work on its environment. The

change of internal energy isA. +32 J

B. -16 J

C. +16 J

D. -3.0 J

The mass of a cruise ship (including passengers and cargo) is 2.2x106 kg. While cruising the

buoyant force is ___ and the net force is ____.

A. 0.0 N, 0.0 N

B. 0.0 N, 2.2x107N

C. 2.2x107N, 2.2x107N

D. 2.2x107N, 0.0 N

The second piston of a hydraulic system has an area 5.0 times larger than the first piston. If 15 N

of force is exerted on the first piston

A. 3.0 N of force will be exerted at the second piston

B. The pressure at the second piston will be 5.0 times smaller than at the first piston.

C. The pressure at the second piston will be the same as at the first piston.

D. None of the above is true

According to the second law of thermodynamics

A. Heat flows spontaneously from cold objects to hot objects

B. It is possible to design a heat engine that produces no waste heat.

C. As entropy increases the amount of disorder decreases.

D. Things tend to become more disordered as time passes

The boiling point of helium is 4.2 K. When 42 kJ of heat is added to a large container of liquid helium at 4.2 K, 2.0 kg of the substance changes from a liquid to a gas. The heat of vaporization of helium

isA. Depends on how much the

temperature of the helium rises

B. Is 5.0 kJ/kg/K

C. Is 84 kJ/kg

D. Is 21 kJ/kg

When 100 g of metal at 130oC is added to 300 g of water at 20oC, the temperature rises to 30oC. What is the specific heat of the metal? (Use

cwater=4.2kJ/kg/oC)

A. 1.3kJ/kg/oC

B. 800J/kg/oC

C. 2.1kJ/kg/oC

D. 4.8kJ/kg/oC

The linear coefficient of expansion of Aluminum is 2.4x10-5(oC)-1. If a 10.000 m rod of aluminum is

heated from 20oC to 220oC it will expand by

A. 4.8 cm

B. 4.8 mm

C. 10.048 m

D. 2.4 mm

Spring potential energy

A. -kx

B. 2p(m/k)1/2

C. ½ kx2

D. ½ mv2

Archimedes’ principle states that the buoyant force equals

A. The density of the object

B. The weight of the portion of the object which is submerged

C. The weight of the un-submerged portion of the object

D. The weight of the displaced fluid

Echoes are an example of wave

A. Interference

B. Polarization

C. Reflection

D. Diffraction

Light strikes a mirror with an incident angle of 40o. The angle between the reflected ray

and the incident ray isA. 40o

B. 50o

C. 80o

D. 100o

A magenta shirt

A. Absorbs blue and red light

B. Reflects blue and red light

C. Reflects green light

D. Reflects cyan and yellow light

The index of refraction of a transparent material is 1.8. The speed of light through

this material isA. 3.0 x 108 m/s

B. 5.4 x 108 m/s

C. 1.2 x 108 m/s

D. 1.7 x 108 m/s

Real images created by mirrors are

A. Always erect

B. “inside” the mirror

C. Occur only when the object is located inside the focal point

D. Are in front of the mirror

Concave (diverging) lenses

A. Form only real images

B. Form only enlarged images

C. Form only inverted images

D. Form only virtual images

Rainbows and prisms split white light into colors by

A. Thin film interference

B. Dispersion

C. Diffraction

D. Pigments

Which of the following CAN form real images

A. Plane mirrors

B. Concave lenses

C. Concave mirrors

D. Convex mirrors

Dispersion occurs because

A. Different wavelengths of light travel at slightly different speeds through a transparent medium.

B. Some colors experience constructive interference

C. Impurities in the prism add colors to the white light.

D. Only visible light experiences refraction

Visible light

A. Is a longitudinal electromagnetic wave

B. Is a transverse mechanical wave

C. Has a longer wavelength than microwaves

D. Transverse oscillations of electric and magnetic fields

A photon is

A. A positively charged particle found in the nucleus of atoms

B. Proof that light does NOT exhibit wave behavior

C. A bundle of electromagnetic energy

D. A type of torpedo

Enlarged virtual images may be formed when

A. The object is located beyond the focal point of a converging lens.

B. The object is inside the focal point of a convex mirror

C. The object is inside the focal point of a concave mirror

D. The image is inverted

A 3.0 cm tall object is located 12 cm from a convex lens with a focal length of 6.0 cm. The image

formed

A. Is virtual and enlarged

B. Is on the same side of the lens as the object

C. Is smaller than the object

D. Can not be projected onto a screen

E. Is real

Number of wave cycles per second

A. Period

B. Frequency

C. Amplitude

D. Hyphen

The properties of the medium determine the ______ of a wave.

A. Frequency

B. Speed

C. Period

D. Amplitude

A car that is heading toward you blows its horn. The Doppler effect explains why

A. The sound is getting louder

B. The wavelength is getting longer

C. The pitch you hear is higher

D. The frequency is decreasing

A wave curving around a barrier or spreading out after going through an

openingA. Refraction

B. Interference

C. Diffraction

D. Resonance

If the frequency of a certain wave is 10 Hz, its period is

A. 0.1 seconds

B. 10 seconds

C. 100 seconds

D. The end of the sentence

Which of the following is not a transverse wave?

A. Sound

B. Light

C. Radio

D. All of these

Increase in amplitude that occurs from driving a system at its natural frequency

A. Refraction

B. Dissonance

C. Resonance

D. Beats

When a wave refracts the ____ does not change

A. Wavelength

B. Speed

C. Amplitude

D. Frequency

Beats occur because of

A. Refraction

B. Interference

C. The Doppler Effect

D. Dispersion

A 680 Hz sound wave travels at 340 m/s in air with a wavelength of

A. 1.0 m

B. 2.0 m

C. 0.5 m

D. 0.25 m

A spring stretches by 0.10 m when some bananas weighing 4.5 N are suspended

from it. The spring constant of the spring is

0%

0%

0%

0% A. 0.45 N-m

B. 4.6 N/m

C. 4.6 J

D. 45 N/m

Water waves in a lake travel 5.0 m in 2.5 s. The period of oscillation is 0.40 s. The

wavelength is

0%

0%

0%

0% A. 5.0 m

B. 1.25 m

C. 0.80 m

D. 2.5 cm

The pitch of a sound depends on

A. Amplitude

B. Speed

C. Frequency

D. Slope

The fundamental resonance in a pipe closed on one end is 440 Hz. The next harmonic is

A. 880 Hz

B. 1.32 kHz

C. 1.76 kHz

D. 440 Hz