Deck 7: Waves

Question 1

Sound waves travel slowest in

A)a vacuum.
B)gases.
C)liquids.
D)solids.

Answer 1

gases.

Question 2

The amplitude of the wave shown in the figure is

A) A.
B) B.
C) C.
D) D.

Answer 2

B.

Question 3

When a sound wave goes from air into water, the quantity that remains unchanged is its

A)speed.
B)amplitude.
C)frequency
D)wavelength.

Answer 3

frequency

Question 4

The lower the frequency of a sound wave, the

A)higher its speed.
B)higher its pitch.
C)louder it is.
D)longer its wavelength.

Question 5

Energy is carried by which one or more of the following ways?

A)sound wave
B)light wave
C)water wave
D)wave in a stretched string
E)All of the above

Question 6

The property of a sound wave that governs its loudness is its

A)frequency.
B)wavelength.
C)speed.
D)amplitude.

Question 7

A wave of amplitude A interferes with another wave of the same kind with the same frequency whose amplitude is also A. The resulting wave

A) has an amplitude of 2A.
B) has an amplitude between 0 and A.
C) has an amplitude between A and 2A.
D) has an amplitude between 0 and 2A.

Question 8

A pure musical note causes a thin wooden panel nearby to vibrate with the same frequency.This is an example of

A)an overtone.
B)diffraction.
C)interference.
D)resonance.

Question 9

An example of a wave that is partly longitudinal and partly transverse is a

A)sound wave.
B)light wave.
C)water wave.
D)wave in a stretched string.

Question 10

In a transverse wave, the individual particles of the medium move

A)in circles.
B)in ellipses.
C)parallel to the direction of travel.
D)perpendicular to the direction of travel.

Question 11

Ultrasound refers to sound whose

A)frequency is too high for most people to hear.
B)wavelength is too long for most people to hear.
C)intensity level is 100 dB or more.
D)frequency has undergone a Doppler shift to a higher one.

Question 12

An example of a purely longitudinal wave is a

A)sound wave.
B)light wave.
C)water wave.
D)wave in a stretched string.

Question 13

A 70-dB sound relative to a 40-dB sound is more intense by a factor of

A)3.
B)30.
C)300.
D)1000.

Question 14

Two waves meet at a time when one has the instantaneous amplitude A and the other has the instantaneous amplitude B. Their combined amplitude at this time is

A) A + B.
B) A - B.
C) between A + B and A - B.
D) indeterminate.

Question 15

The greater the decibel (dB) level of a sound wave, the

A)higher its frequency is.
B)longer its wavelength is.
C)louder it is.
D)farther away its source is.

Question 16

Which one or more of the following effects occur in all types of wave?

A)refraction
B)reflection
C)diffraction
D)the Doppler effect
E)All of the above

Question 17

The bending of waves around the edge of an obstacle in their path is an example of

A)refraction.
B)reflection.
C)diffraction.
D)the Doppler effect.

Question 18

The greater the amplitude of a wave, the greater its

A)frequency.
B)wavelength.
C)speed.
D)energy.

Question 19

A sound wave whose frequency is 50 Hz

A)has a relatively short wavelength.
B)has a relatively long wavelength.
C)is very soft.
D)is very loud.

Question 20

The wavelength of the wave shown in the figure is

A) A.
B) B.
C) C.
D) D.

Question 21

Polarization is similar to

A)refraction.
B)interference.
C)diffraction.
D)None of the choices are correct.

Question 22

The image formed by a diverging lens of a real object is always which one or more of the following?

A)virtual
B)real
C)inverted
D)larger than the object

Question 23

Light of which of the following colors has the lowest frequency?

A)red
B)blue
C)yellow
D)green

Question 24

The ionosphere

A)reflects radio waves.
B)is responsible for the blue color of the sky.
C)is responsible for rainbows.
D)is caused by the exhausts of high-altitude aircraft.

Question 25

Light of which of the following colors has the shortest wavelength?

A)red
B)blue
C)yellow
D)green

Question 26

You are looking at the bottom of a lake 1.2 m deep from a boat.To you the lake seems to be

A)less than 1.2 m deep.
B)1.2 m deep.
C)more than 1.2 m deep.
D)Any of these choices could be correct, depending on the height of the sun.

Question 27

A converging lens of focal length f produces a virtual image of a real object when the object is

A)closer than f from the lens.
B)at the distance f from the lens.
C)farther than f from the lens.
D)at any distance from the lens.

Question 28

Relative to the radio signals sent out by a spacecraft headed away from the earth, the signals that are received on the earth have

A)a lower speed.
B)a lower frequency.
C)a shorter wavelength.
D)all of these properties.

Question 29

The image a camera lens forms on the film is

A)always real.
B)always virtual.
C)sometimes real and sometimes virtual.
D)neither real nor virtual.

Question 30

A converging lens of focal length f produces a real image of a real object when the object is

A)closer than f from the lens.
B)at the distance f from the lens.
C)farther than f from the lens.
D)at any distance from the lens.

Question 31

Of the following kinds of waves, the ones that cannot travel through a vacuum are

A)X-rays.
B)radio waves.
C)light waves.
D)sound waves.

Question 32

The image the lens of the eye forms on the retina is

A)real and erect.
B)real and inverted.
C)virtual and erect.
D)virtual and inverted.

Question 33

A changing electric field gives rise to

A)a magnetic field.
B)electromagnetic waves.
C)sound waves.
D)nothing in particular.

Question 34

Relative to its object, a real image formed by a lens is always

A)erect.
B)inverted.
C)smaller.
D)larger.

Question 35

Electromagnetic waves transport which one or more of the following?

A)electric charge
B)alternating current
C)energy
D)wavelength

Question 36

A frequency that is not an overtone of the fundamental frequency F is

A)F/2.
B)2F.
C)3F.
D)4F.

Question 37

When a real object is the distance f from a converging lens,

A)the image is virtual, erect, and larger than the object.
B)the image is real, inverted, and larger than the object.
C)the image is real, inverted, and the same size as the object.
D)no image is formed.

Question 38

Of the following, the highest index of refraction is found in

A)air.
B)water.
C)glass.
D)diamond.

Question 39

In an electromagnetic wave, the electric field is

A)parallel to both the magnetic field and the wave direction.
B)perpendicular to both the magnetic field and the wave direction.
C)parallel to the magnetic field and perpendicular to the wave direction.
D)perpendicular to the magnetic field and parallel to the wave direction.

Question 40

Of the following kinds of waves, those that cannot be polarized are

A)X-rays.
B)radio waves.
C)light waves.
D)sound waves.

Question 41

Sound waves whose frequency is 300 Hz have a wavelength relative to sound waves in the same medium whose frequency is 900 Hz that is

A)one-third as great.
B)the same.
C)three times as great.
D)nine times as great.

Question 42

Radio amateurs are permitted to communicate on the "10-meter band." What frequency of radio waves corresponds to a wavelength of 10 meters? The speed of radio waves is 3 * 10⁸ m/s.

A)3.3 * 10^-8 Hz
B)3.0 * 10⁷ Hz
C)3.3 * 10⁷ Hz
D)3.0* 10⁹ Hz

Question 43

Relative to the focal length of a wide-angle camera lens, the focal length of a telephoto lens is

A)shorter.
B)the same.
C)longer.
D)Any of theses choices could be correct, depending on the camera.

Question 44

The speed of light in a transparent plastic whose index of refraction is 1.5 is

A)1.5 * 10⁸ m/s.
B)2 * 10⁸ m/s.
C)3 * 10⁸ m/s.
D)4.5 * 10⁸ m/s.

Question 45

The musical note A has a frequency of 440 Hz and its wavelength in seawater is 3.5 m.The speed of sound in seawater is

A)80 m/s.
B)126 m/s.
C)1540 m/s.
D)3 * 10⁸ m/s.

Question 46

To an astronaut in orbit around the earth the sky appears

A)red.
B)blue.
C)white.
D)black.

Question 47

The setting sun appears red because its light is

A)refracted.
B)reflected.
C)diffracted.
D)scattered.

Question 48

A medal in a plastic cube whose index of refraction is 1.5 appears to be 20 mm below the upper surface of the cube.The depth of the medal is actually

A)10 mm.
B)13 mm.
C)20 mm.
D)30 mm.

Question 49

When the American flag is viewed with red light it appears

A)all red.
B)red, white, and blue.
C)red and blue.
D)red and black.

Question 50

Light of which of the following colors is scattered most in the atmosphere?

A)red
B)blue
C)yellow
D)green

Question 51

Dispersion is the term used to describe the

A)splitting of white light into its component colors in refraction.
B)propagation of light in straight lines.
C)bending of a beam of light when it goes from one medium to another.
D)bending of a beam of light when it strikes a mirror.

Question 52

A boat at anchor is rocked by waves whose crests are 50 m apart and whose speed is 10 m/s.These waves reach the boat once every

A)0.2 s.
B)5 s.
C)50 s.
D)500 s.

Question 53

The property of light waves that leads to the phenomenon of color is

A)speed.
B)amplitude.
C)acceleration.
D)frequency.

Question 54

The Swedish flag is blue and yellow.When viewed with blue light it appears

A)all blue.
B)blue and yellow.
C)blue and black.
D)white and yellow.

Question 55

Ocean waves whose period is 8 s are observed to have a wavelength of 100 m.Their speed is

A)0.08 m/s.
B)12.5 m/s.
C)100 m/s.
D)800 m/s.

Question 56

Sound waves whose frequency is 300 Hz have a speed relative to sound waves in the same medium whose frequency is 900 Hz that is

A)one-third as great.
B)the same.
C)three times as great.
D)nine times as great.