physics final

Select the correct equation that shows that this is equivalent to about 6300 kJ .

(1500kcal)(4.19kJ/kcal)=6285kJ

Which one of these represents the largest amount of energy?

1 Calorie

Rank the magnitudes of the following units of thermal energy from greatest to least:

1 Calorie, 1 calorie, 1 joule

Rank from greatest to least the volumes of water of the same mass at the following temperatures:

10c, 0c, 4c

Two speakers face each other, and they each emit a sound of wavelength λ. One speaker is 180∘ out of phase with respect to the other. If we separate the speakers by a distance 1.5λ, how far from the left-most speaker should we place a microphone in order to pick up the loudest sound? Ignore reflections from nearby surfaces. Select all that apply.

12 λ λ 0λ

Now, for parts F-I, you will investigate how the period of oscillation depends on the properties of the pendulum.The period of oscillation is the amount of time it takes for the pendulum to take a full swing, going from the original angle to the other side, and returning to the original angle. You can determine the period by selecting other tools, which gives you a stopwatch. With the pendulum swinging, you can start the stopwatch when the pendulum is at its original angle and time how long it takes to complete 10 swings. The period will be this time interval divided by 10 (this method is more accurate than trying to time one swing).Set the length of the pendulum to 1.0 m and the mass to 1.0 kg. Click Reset, and then drag the pendulum to an angle (with respect to the vertical) of 30∘ and release it. What is the period of oscillation?

2.0 s

Which one of these cites the lowest temperature?

270 K

How many nodes, not including the endpoints, are there in a standing wave that is two wavelengths long? Three wavelengths long?

3, 5

What beat frequency will occur when a 370-Hz and a 374-Hz sound source are sounded together?

4 Hz

Rank the beat frequency from highest to lowest for the following pairs of sounds: a. 143 Hz, 146 Hz b. 173 Hz, 179 Hz c. 234 Hz, 264 Hz d. 453 Hz, 486 Hz Rank from highest to lowest. To rank items as equivalent, overlap them.

453 Hz, 486 Hz 234 H z , 264 H z 173 H z , 179 H z 143 H z , 146 H z

How fast does a 200-Hz sound wave with a wavelength of 2.5 m travel?

500 ms

if you walk at 1 km/h down the aisle toward the front of a train that moves at 60 km/h, what is your speed relative to the ground?

61 km/h

How many shells are represented in the presently known periodic table?

7

Distinguish between a calorie and a Calorie.

A Calorie is 1000 calories.

Now, keep the mass fixed to any value you choose and measure the period for several different pendulum lengths. How does the period of the pendulum depend on the length?

A longer pendulum has a longer period.

How does a molecule differ from an atom? Give an example.

A molecule is composed of two or more atoms bonded together: H2O.

How does a sine curve describe a wave?

A sine curve is a pictorial representation of a wave.

As the text cites, atoms are incredibly tiny, numerous, perpetually moving, and what else?

Ageless

What is the same in Einstein's first postulate?

All laws of nature in all uniformly moving frames of reference

From greatest to least, rank the wires in how much they'll sag on a hot summer day. A: Copper, α=17×10−6/∘C B: Aluminum, α=24×10−6/∘C C: Steel, α=11×10−6/∘C

Aluminum, copper, steel

What is a compound? Cite two examples.

Atoms of different elements with bonds between them: NaCl and H2O

What is a mixture? Cite two examples.

Atoms pressed together without bonding: air and salt and sand

How does the cooler air above the lake affect the movement of sound at night?

Because it is colder just above the surface and warmer higher above, the sound wave is refracted toward the ground.

Why does the strip behave as it does when Dr. Hewitt heats it up?

Both metals expand unequally.

Why does sound sometimes refract under water?

Changing temperature changes the speed of sound in water.

Distinguish between constructive interference and destructive interference.

Constructive interference occurs when the crests of two waves add together. Destructive interference occurs when a crest of one wave is reduced by the trough of another.

When the temperature of ice-cold water is increased slightly, does it undergo a net expansion or a net contraction?

Contraction

What is the cause of refraction?

Different speeds of sound in a medium

Which two factors determine the natural frequency of an object?

Elasticity and shape

Since atoms are mostly empty space, why don't we fall through a floor we stand on?

Electrons in one atom repel the electrons in another.

Each of the following items states a temperature, but does not tell you whether the temperature is measured on the Fahrenheit, Celsius, or Kelvin scale. Match the items to the appropriate temperature scale.

F- a hot summer day might be 100, ice cream is stored in freezers at 26 C- water freezes into ice at 0, liquid water boils at 100, a typical room temperature is 24 K- the coldest possible temperate is 0, water boils into gas phase at 373.15

How are frequency and period related to each other?

Frequency and period are reciprocals.

What is the evidence that dark matter exists?

Gravitational forces within galaxies are too great to be accounted for with ordinary matter.

Which of the following is an element?

Hydrogen

Where in the atom is most of its mass concentrated? What is this mass composed of?

In the nucleus as protons and neutrons

Distinguish between infrasonic and ultrasonic sound waves.

Infrasonic is too low in frequency (below 20 Hz) for humans to hear, whereas ultrasonic is too high (above 20,000 Hz).

What happens when Dr. Hewitt heats up the strip?

It bends.

What factors does the speed of sound depend upon? What are some factors that it does not depend upon?

It depends on temperature and humidity, not on loudness and frequency.

What is the difference in the speed of sound on a warm day versus on a cold day?

It is faster on a warm day and slower on a cold day.

Which generally expands more for an equal increase in temperature: solids or liquids?

Liquids generally expand more than solids.

Distinguish between mass number and atomic mass.

Mass number is the number of nucleons; atomic mass is the total mass of an atom.

Does the medium in which a wave travels move with the wave?

No

In the Doppler effect, does frequency change? Does wave speed change?

Only frequency changes.

What is the relationship between frequency and pitch?

Pitch is the human perception of sound frequency.

Select to show the energy of pendulum 1. Be sure that friction is set to none. Drag the pendulum to an angle (with respect to the vertical) of 30∘, and then release it. When the pendulum is at −30∘, what form(s) of energy does it have?

Potential energy

Select the correct equations that show that the amount of heat needed is 1500 kcal ( 1500 Cal).

Q=cmΔT=(1kcal/(kg⋅∘C))(75kg)(20∘C)=1500kcal

Select the correct equations that show that the amount of heat needed to raise the temperature of a 22-kg piece of steel from 0 ∘C to 100 ∘C is 990,000 J.

Q=cmΔT=(450J/kg⋅∘C)(22kg)(100∘C−0∘C)=990,000J

What is an echo?

Reflection of sound is an echo.

Relative to solids and liquids, how does air rank as a conductor of sound?

Relative to solids and liquids, air is a poor conductor of sound.

Which investigator is credited for discovering Brownian motion?

Robert Brown

Drag the pendulum to an angle (with respect to the vertical) of 30∘, and then release it. Select to show the acceleration vector. With the pendulum swinging back and forth, at which locations is the acceleration equal to zero?

The acceleration is never equal to zero as it swings back and forth.

Given a wave of a particular wavelength and amplitude, what must be the amplitude, wavelength, and phase change of a wave you add to this wave to create a wave of twice the amplitude?

The added wave must have the same amplitude, the same wavelength, and a phase difference of 0 degrees with respect to the original wave.

Given a wave of a particular wavelength and amplitude, what must be the amplitude, wavelength, and phase change of a wave you add to the existing wave to completely destroy it?

The added wave must have the same amplitude, the same wavelength, and a phase difference of 180 degrees with respect to the original wave.

For maximum constructive interference between two waves, how must their crests and troughs align with each other?

The crests and troughs of one wave should align with the crests and troughs of the other wave respectively.

For complete destructive interference between two waves, how must their crests and troughs align with each other?

The crests and troughs of one wave should align with the troughs and crests of the other wave respectively.

If you place a Styrofoam cup on the table and a bunch of BBs move around it randomly, what will happen to the cup, and why?

The cup will move randomly in different directions because the BBs will exert unequal forces on the cup in different directions.

How is the energy value of foods determined?

The food is burned and the energy released is measured.

What happens to the frequency of the wave if you increase the wavelength, keeping the velocity of the wave constant?

The frequency decreases.

What happens to the frequency of the wave if you increase the wave velocity, keeping the wavelength of the wave constant?

The frequency increases.

When the bug that is creating waves swims forward, how does the frequency of the wave some distance away behind the bug compare with the frequency produced by a stationary bug?

The frequency of the wave some distance away behind the bug is less than the frequency of the wave produced by a stationary bug.

When the bug that is creating waves swims forward, how does the frequency of the wave some distance away in front of the bug compare with the frequency of the wave produced by a stationary bug?

The frequency of the wave some distance away in front of the bug is greater than the frequency produced by a stationary bug.

When the bug is stationary and creating waves, how does the frequency of the wave some distance away from the bug compare with the frequency of the vibration of the bug?

The frequency of the wave some distance away is equal to the frequency of the vibration of the bug.

Northeastern Canada and much of Europe receive about the same amount of sunlight per unit area. Why, then, is Europe generally warmer in the winter?

The gulf stream carries warm, high heat capacity water past the west coast of Europe.

When you listen to a radio, why do you hear only one station at a time rather than all stations at once?

The natural frequency of the electronics is tuned to resonate with the frequency of one station.

Why did the particles jiggle around?

The particles were struck by atoms, but unequally on different sides.

Keeping the length of the pendulum fixed, determine the period for a few different masses. (Alternatively, you can set up two pendulums by selecting Show 2nd pendulum. Adjust the lengths to be the same, and have one pendulum with a higher mass. You can release one and then release the other, with the same angle, when the first one is back at that angle.) How does the period of the pendulum depend on mass?

The period is independent of the pendulum's mass.

How does the period of oscillation depend on the initial angle of the pendulum when released? (Be sure to measure the period for initial angles much greater than 30∘.)

The period is longer when the initial angle is greater.

Now, change the planet where the experiment takes place to see how the period of oscillation depends on the acceleration due to gravity, g (on Earth, g≈10 m/s/s; g is larger than this value on Jupiter and smaller than this value on the Moon). How does the period of oscillation depend on the value of g?

The period of oscillation is shorter on planets with a higher value of g.

Compared with the energy it takes to separate oxygen and hydrogen from water, how much energy is released when they recombine?

The same amount of energy is released when they recombine.

A cat can hear sound frequencies up to 70,000 Hz. Bats send and receive ultra-high-frequency squeaks up to 120,000 Hz. Which hears sound of shorter wavelengths, cats or bats?

The shorter wavelengths are heard by bats.

How does the direction of sound travel compare to the shapes of the sound waves?

The sound is at right angles to the waves.

What is the result of a mirror image of a sound signal combining with the sound itself?

The sound is cancelled when added to its mirror image.

When the bug that is creating waves swims in the direction of the waves, how does the speed of the wave some distance away in front of the bug compare with the speed of the wave created by a stationary bug?

The speed of the wave some distance away is equal to the speed of the wave due to a stationary bug.

Why will a struck tuning fork sound louder when it is held against a table?

The table is forced to vibrate, and its large surface vibrates more air than the tuning fork.

Why did the campers in Dr. Hewitt's story hear the sound of the campers across the lake more clearly at night than during the day?

The temperature change from cold at the surface to warm at the top changed the shape of the sound waves.

With the pendulum swinging back and forth, how does the tension of the rope compare to the force of gravity when the angle is 0∘?

The tension is greater than the force of gravity.

Drag the pendulum to an angle (with respect to the vertical) of 90∘, and then release it. With the pendulum swinging back and forth, where is the tension equal to zero

The tension is zero at the angles +90∘ and −90∘.

What is meant by the period of a pendulum?

The time interval of a to-and-fro swing

How do the waves of sound travel on the night that produces the temperature inversion, and why?

The waves bend toward the ground because it is warmer above and colder lower below, and waves travel more slowly through the colder air.

Is there a distinction between thermal energy and internal energy? Which term do physicists prefer?

Thermal energy emphasizes heat flow, whereas internal energy is the grand total of all energies inside a substance. Physicists prefer internal energy.

What occurs when a proton and an antiproton meet?

They annihilate each other.

How does this compare with the heat needed to raise the temperature of the same mass of water through the same temperature difference?

This value is less than the heat needed to raise the temperature of the same mass of water through the same temperature difference.

Which of the following changes would make the water balloon more likely to pop? (Ignore effects of convection within the fluid.) Select all that apply.

Use a thicker balloon. Use a liquid that has a lower heat capacity than water.

What is the relationship among frequency, wavelength, and wave speed?

Wave speed is frequency multiplied by wavelength.

How do matter and antimatter differ?

When matter and antimatter meet, they annihilate in a flash of energy.

How can you double the frequency of a wave if you have control over both the wavelength and the wave velocity?

You can either halve the wavelength, keeping the wave speed constant; or double the wave speed, keeping the wavelength constant.

What kind of strip is Dr. Hewitt holding in his hand?

a strip consisting of brass on one side and steel on the other, welded together

Each figure below shows a spaceship moving past your spaceship ("YOU") at the indicated speed. Imagine that you watch the other spaceship as its clock ticks off one second. Rank the figures according to how much time you would say passes (on your own ship) while the other ship's clock ticks off one second, from the shortest to the longest amount of time.

a. .85, .8, .75, .7 b. .85, .8, .75, .7 c. both spaceships are the same length

A weight suspended from a spring is seen to bob up and down over a distance of 24 cm twice each second. a. What is its frequency? b. What is its period? c. What is its amplitude?

a. 2.0 Hz b. 0.50 s c. 12 cm

Consider the following atoms: A. Magnesium. B. Niobium. C. Dubnium. D. Tantalum. Consult the periodic table and rank these atoms, from most to least, by their mass. Rank from most to least. To rank items as equivalent, overlap them.

a. Dubnium Tantalum Niobium Magnesium b. Dubnium Tantalum Niobium Magnesium c. Dubnium Tantalum Niobium Magnesium

The atomic masses of two isotopes of cobalt are 59 and 60. What is the number of protons in each? Express your answers as integers separated by a comma.

a. cobalt-59, cobalt-60 = 27,27 protons b. cobalt-59, cobalt-60 = 32,33 neutrons c. cobalt-59, cobalt-60 = 27,27 electrons

Consider a block of mass m attached to a spring with force constant k, as shown in the figure(Figure 1). The spring can be either stretched or compressed. The block slides on a frictionless horizontal surface, as shown. When the spring is relaxed, the block is located at x=0. If the block is pulled to the right a distance A and then released, A will be the amplitude of the resulting oscillations. Assume that the mechanical energy of the block-spring system remains unchanged in the subsequent motion of the block. a. After the block is released from x=A, it will b. If the period is doubled, the frequency is c. An oscillating object takes 0.10 s to complete one cycle; that is, its period is 0.10 s. What is its frequency f? d. If the frequency is 40 Hz, what is the period T ? e. Which points on the x axis are located a distance A from the equilibrium position? f. Suppose that the period is T. Which of the following points on the t axis are separated by the time interval T? g. What is the period T ? h. How much time t does the block take to travel from the point of maximum displacement to the opposite point of maximum displacement? i. What distance d does the object cover during one period of oscillation? j. What distance d does the object cover between the moments labeled K and N on the graph?

a. move to the left until it reaches x=−A and then begin to move to the right. b. halved c. f = 10 Hz d. T = 0.025 s e. both R and Q f. K and P g. T = 0.02 s h. 0.01 s i. 0.48 m j. 0.36 m

Drag the pendulum to an angle (with respect to the vertical) of −30∘ and then release it. Where is the pendulum swinging the fastest?

at 0∘

The periodic table of the elements is a list of __________.

atoms

Use a ruler and rank these waves from most to least for frequency.

cbda

Use a ruler and rank these waves from most to least for period.

dabc

Use a ruler and rank these waves from most to least for wavelength.

dabc

Use a ruler and rank these waves from most to least for amplitude.

dbac

How about the wavelength reaching your ear?

decreases

what classical idea about space and time did einstein reject?

einstein rejected the idea that space and time are independent

A shock wave occurs when an aircraft travels _________.

faster than the speed of sound

how measurements of time differ for events in a frame of reference that moves at 50% of the speed of light relative to us? at 99.5% of the speed of light relative to us?

for .50c, time dilates to 1.15 times the proper time, for .995c, time dilates to 10 times the proper time

To become a negative ion, does an atom lose or gain an electron?

gains

An oceanic depth-sounding vessel surveys the ocean bottom with ultrasonic waves that travel 1530 m/s in sea-water. The time delay of the echo to the ocean floor and back is 5.65 s . Find the depth of the water directly below the vessel. Express your answer with the appropriate units.

h = 4320 m

An important feature of atoms is that they __________.

have wave properties

If a pendulum is shortened, does its frequency increase or decrease? What about its period?

increase, decrease

A railroad locomotive is at rest with its whistle shrieking, then starts moving toward you. Does the frequency of sound that you hear increase, decrease, or stay the same?

increases

Time is required for light to travel along a path from one point to another. If this path is seen to be longer because of motion, what happens to the time it takes for light to travel this longer path?

it takes longer

imagine that you are located on earth while a spaceship travels from earth to the star vega at constant velocity of .8c. the following times describe quantities that, according to einsteins special theory of relativity, would be either larger, smaller, or the same as their rest values

larger- one second on your clock as seen by spaceship passengers, one second on a spaceship clock as seen by you, you mass as measured by spaceship passengers, mass of the spaceship as measured by you smaller- distance from earth to vega as measured by spaceship passengers, length of the spaceship as measured by you same- speed of the spaceships headlight beam as measured by you

To become a positive ion, does an atom lose or gain an electron?

loses

The charge in the nucleus of an antimatter hydrogen atoms is __________.

negative

Suppose that we replace the aluminum with a mystery metal and repeat the experiment in the video. As in the video, the mass of the metal is the same as that of the water. Room temperature is about 20∘C before the start of the experiment. The water heats up to 40∘C, and the mystery metal heats up to 80∘C. Compared to that of water, the heat capacity of our mystery metal is

one-third as great.

When a flashing light source approaches you, does the speed of light or the frequency of light - or both - increase?

only frequency increases

Dark matter is considered to be __________.

plentiful in the universe

Rank the number of shells in these noble-gas atoms from most to least: A. Argon. B. Radon. C. Helium. D. Neon. Rank from most to least. To rank items as equivalent, overlap them.

radon argon' neon helium

What did Robert Brown see under the microscope?

specks of dust moving around

How about the speed of sound in the air between you and the locomotive?

stays the same

how does the distance that light travels in earths frame of reference change as the speed of the spaceship increases?

the distance that light travels in earths frame of reference increases

Inside the moving compartment of Figure 35.4, light travels a certain distance to the front end and a certain distance to the back end of the compartment. How do these distances compare as seen in the frame of reference of the moving rocket?

the distances traveled by light are the same

what is constant in einsteins second populate?

the speed of light in a vacuum

how does the time measured in earth's frame of reference change as the speed of the spaceship increases?

the time measured in the earths frame of reference increases

how does the time measured in the spaceship's frame of reference change as the speed of the spaceship increases?

the time measured in the spaceship's frame of reference does not change

consider again the spaceships from parts a and b. suppose that at rest, both you and a passenger on another spaceship have the same heart rate of 60 beats per minute. how will you and the passenger on the other spaceship observe each others heart rates as you pass by in your spaceships?

you would observe that the other passenger in the spaceship has a slower heart rate than you do, and she would observe you have a slower heart rate than hers