Physics Final Exam Review

A curve ball in baseball curves because of A. lift forces. B. drag forces. C. gravitational forces. D. buoyant forces.

A

Aerodynamic forces consist of A. drag and lift. B. drag, lift and buoyancy. C. drag and gravity. D. lift and drop.

A

In a popular classroom demonstration, a cotton ball is placed in the bottom of a strong test tube. A plunger fits inside the tube and it makes an air - tight seal. It is then pushed down very rapidly, and the cotton flashes and burns. This happens because A. when the air was compressed its temperature increased. B. friction between the plunger and the tube ignited the cotton. C. cotton contains a pressure - sensitive substance that burns upon impact. D. it's one of those demos that nobody understands.

A

Suppose you "think outside the box" and design a guitar with strings which all have the same thickness, length and density. Which of the following designing issues must you also consider? A. The strings must be able to withstand a wide range of tensions in order to produce the notes needed. B. The strings will vibrate too fast to make any noticeable sound. C. The strings will now make their best sound with longitudinal waves. D. The strings must be plucked only at certain spots along their length.

A

The pressure in a water pipe may not necessarily be lower in regions where the water moves faster when A. the pipe is not level B. the pipe is level. C. the pipe is in zero gravity. D. the pipe is in free fall.

A

You are on your honeymoon but the only thing you can notice is that waves which strike the shore do so traveling directly towards it. This is an effect of A. refraction, because as the water shallows the waves are bent so as to travel more directly towards the shore. B. interference because the shore is sending out waves which straighten out the water waves. C. friction with the shore, because all the sideways traveling momentum the wave has is removed with friction. D. reflection, because the waves reflect off the ocean bottom and get straightened out.

A

You are taking a shower in your dormitory when someone flushes a toilet nearby. The pressure in the cold water line drops and you find yourself showering in what feels like molten lava. This loss of cold water pressure occurs when the toilet lets cold water flow through the pipes delivering it to the bathroom and the water's speed in those pipes increases. Assuming all the piping to be about on the same level, the cold water's faster motion in the delivery pipes reduces its pressure in the shower head because faster moving water A. has less pressure than slower moving water. B. has less kinetic energy than slower moving water. C. has less gravitational potential energy than slower moving water. D. losses more energy to viscous drag as it flows through the delivery pipes.

A

The neighborhood children are playing and one has lost a pocketful of change. As a result they all decide to do a close inspection of the sidewalk. They notice that there are gaps in between the sidewalk filled with a felt - like material. These gaps will prevent A. high stress due to electron "collisions" B. high stress due to thermal expansion. C. high stress due to brittleness D. high stress due to the weight of the sidewalk

B

The surface of the moon is exposed to full solar radiation because it has no atmosphere. Why then does the moon not heat up endlessly until it disintegrates? A. Convection in the soil carries energy away. B. Its temperature rises until it is able to radiate heat away into space as fast as it arrives from the sun. C. It has disintegrated but the light just hasn't reached us yet. D. Because it is isolated from the sun by empty space, the sun's heat can't reach it (only light can) and they don't experience any changes in temperature.

B

Why does a tidal cycle take more than 12 hours? A. Earth's rotation B. The Moon orbits the Earth. C. Earth moves around the sun. D. Friction of water with land

B

You are a superb proposal writer and convince NASA to let you tag along to Mars (where gravity is less than half that on Earth) with a pendulum clock in order to study gravity. Compared to how it would be on Earth, the time it takes for the pendulum to compete one cycle will be A. shorter. B. longer. C. the same. D. zero.

B

You decide to attend an amusement park which has a ride where you are strapped into a chair which is in turn firmly attached to a plastic cable. You are released and you bounce up and down as a harmonic oscillator—a mass on the end of spring. Next in line is somebody who weighs twice as much as you do. When the heavier person goes on the ride, you notice that A. both of you will have the same period, regardless of how high you bounce. B. the heavier rider will have a longer period than the lighter one. C. the two riders will have the same period, as long as the heights of their bounces are the same. D. the heavier rider will have a shorter period than the lighter one.

B

multiple choice question The gulf stream is one of nature's ways of transferring energy through A. conduction. B. convection. C. transmission. D. radiation.

B

The pressure in a water pipe is always lower in regions where the water moves faster only when A. the pipe increases in altitude towards the faster fluid end B. the pipe is level. C. anything other than water is in the pipe D. the pipe is made of plastic

B.

A popular classroom demonstration involves placing a paper cup with water in it on a burner, and boiling the water in the cup. Although part of the cup may burn, the part containing the water does not because A. paper is a poor conductor of heat. B. it all happens too quickly for the paper to burn. C. the water absorbs most of the heat from the flame. D. the evolving steam burns the paper on the cup above the water line.

C

In making ice cream, the flavored cream is in a container in contact with ice. In order to freeze the ice cream why is it essential to make the ice melt at a very low temperature? A. Liquid water has a high specific heat. B. The melted ice makes it easier for the air to remove energy from the ice cream. C. The low temperature of the ice as well as its melting removes energy from the flavored cream, causing it to freeze. D. It is easier to stir things around with the ice melted.

C

You open the refrigerator in your room and put in a case of room-temperature root beer. After an hour, the root beer is ice cold. If your room air did not exchange any heat with the outdoor air during that time, the room air will be A. colder because the refrigerator reverses natural heating, so that things get colder rather than hotter. B. colder because as the refrigerator struggles to cool the root beer, some of the cold it produces inevitably leaks out into the room as the result of imperfect insulation. C. warmer because the refrigerator will have pumped heat out of the root beer and into the room air. D. warmer because some of the heat from the root beer inevitably leaks out into the room as the result of imperfect insulation.

C

It is a warm summer day and you are having lunch outdoors on a patio. A window air conditioning unit hums quietly nearby as it cools an office inside the building. Your friend notices that the unit's outdoor part is emitting a considerable amount of heat and comments on how strange that is. You explain correctly that the air conditioner's outside part is emitting the heat A. it produces from the electricity it consumes. B. that is left over when it converts thermal energy from the inside air into electricity. C. it removes from the inside air and the heat it produces from the electricity it consumes. D. it produces during its defrost cycle; when it warms up its evaporator to remove ice that forms because of the humidity.

C???

Flowing honey is less likely to become turbulent than flowing water because A. honey's large density favors laminar flow. B. water's large viscosity favors turbulent flow. C. water's large pressure favors turbulent flow. D. honey's large viscosity favors laminar flow.

D

Star A is yellow, star B is blue, and star C is red. Rank the temperatures of these stars based on their colors from hotest to coldest. A. A, B, C B. B, C, A C. C, B, A D. B, A, C E. A, C, B

D

Explain why, in the condenser of an air conditioner the coils heat up

In the condenser, the coolant condenses. This phase change requires that heat flows to the coolant's surroundings so they get warmer.

Explain why, in the evaporator of an air conditioner the coils cool down

In the evaporator, the coolant evaporates. This phase change absorbs heat from the fluid's surroundings.