Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

PHY 9B > Final > Flashcards

Final Flashcards

1
Q

For a longitudinal running wave that appears when you start shaking a long spring at one end, is the wave speed the same as the speed of any coil of the spring?

A. Yes, the wave speed is the same as the speed of the oscillating coils
B. No, the wave speed is different from the speed of the coils

A

B. No, the wave speed is different from the speed of the coils

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

A divergent lens forms an image of the object. How do you describe your image?

A.Depends on how the object is placed with respect to the focal point. 
B.Always Real inverted 
C.Always Real erect 
D.Always Virtual inverted
 E.Always Virtual erect
A

E.Always Virtual erect

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q 
At a certain depth of the lake the absolute pressure is p. At twice this depth will the absolute
pressure be equal to
A. 2p
B. larger than 2p
C. less than 2p
D. still equal p
A

C. less than 2p

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

You are listening a music from a speaker located at a distance 4 m away. If you approach
the speaker by 2 m the intensity of the sound
A. Increases twice
B. Increases four times
C. Increases eight times
D. Increases as log(2)
E. Will not change.

A

Solution. The sound intensity is inversely proportional to the distance therefore if you get twice closer it will
increase four times. Answer B.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q 
X-ray diffraction is used to determine
A. Velocity of light in the medium
B. Distances between atoms in solids
C. Spectrum of light wavelengths emitted by a source
D. Refractive index of the medium
E. All of the above
A

B. Distances between atoms in solids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

When an object with a hole undergoes thermal expansion, the hole

A

will expand

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

When two ideal gases are mixed and reach thermal equilibrium
A. They have the same temperatures
B. They occupy the same volume
C. They have the same average kinetic energy
D. All of the above
E. None of the above

A

D. All of the above

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

A player bounces a basketball on the floor compressing it to 80% of its original volume.
The air inside the ball is originally at a temperature of 20 degrees C and a pressure of 2 atm. What temperature
does the air in the ball reach at its maximum compression?
Steps to solve

A

use ratio of heat capacities formula to get y. Then use the ration of temperatures to find t

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

A rock with mass m=3 kg is suspended from the roof of an elevator by a light cord. The
rock is totally immersed in a bucket of water that sits on the floor of the elevator, but the rock does not touch the
bottom or the sides of the bucket.
a) When the elevator is at rest, the tension in the cord is 21 N. Calculate the volume of the rock.
b) Derive the expression for the tension in the cord when the elevator
c) Derive the expression for the tension in the cord when the elevator is accelerating downward with an
acceleration magnitude a and calculate the value of the tension for a=2.5 m/s2

A

a) First write down what forces are acting and in what direction. We need to find the Buoyant force. When we get this, we can solve for mass of water and using the fact that density of water is 997 kg/m^3, we can solve for volume of water.
b) First write down what forces are acting and in what direction and then use F=ma
c) same thing just account for sign

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

For a transverse wave on a string is the wave speed the same as the speed of any
particle of the string?
A. Yes, the wave speed is the same as the speed of the particles
B. No, the wave speed is different from the speed of the particles

A

B. No, the wave speed is different from the speed of the particles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q
  1. The four strings on a violin have different thicknesses but all are under
    approximately the same tension. Do waves travel faster on the thick or the thin
    strings?
    A. Waves travel faster on the thick strings
    B. Waves travel faster on the thin strings
    C. Waves have the same speed on all strings
A

B. Waves travel faster on the thin strings

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q
  1. If you stretch a rubber band and pluck it, you hear a (somewhat) musical tone.
    How does the frequency of this tone change as you stretch the rubber band further?
    A. The frequency increases
    B. The frequency decreases
    C. The frequency does not change.
A

A. The frequency increases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q
  1. A musical interval of an octave corresponds to a factor of 2 in frequency. By what
    factor must the tension in a guitar string be increased to raise its pitch one octave.
    A. By a factor of 2
    B. By a factor of 4
    C. By a factor of 8
A

B. By a factor of 4

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

When sound travels from air to water
A. Frequency changes, wavelength and speed are the same
B. Wavelength changes, frequency and speed are the same
C. Both wavelength and speed change, the frequency is the same

A

C. Both wavelength and speed change, the frequency is the same

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

The hero of a western movie listens for an oncoming train by putting his ear to the
track. Does this method give an earlier warning of the approach of the train than
just listening in the usual way?
A. No, the hero just wants to look cool.
B. No, since the speed of sound in air is larger than the speed of sound in metallic
track
C. Yes, because the speed of sound in metallic track is larger than that in the air

A

C. Yes, because the speed of sound in metallic track is larger than that in the air

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

When both ends of the organ pipe are open, a standing air wave is formed with
A. Displacement nodes at both ends.
B. Pressure fluctuation nodes at both ends.
C. Pressure fluctuation node at one end and displacement node at another.

A

B. Pressure fluctuation nodes at both ends.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

When one end of the organ pipe is open and another one is closed, a maximum
wavelength of the standing air wave is
A. The same as the length of the pipe
B. Twice as much as the length of the pipe
C. Four times as much as the length of the pipe

A

C. Four times as much as the length of the pipe

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

A sound source and a listener are both at rest but a strong wind is blowing from the
source towards the listener. Is there a Doppler effect?
A. Yes
B. No.

A

B. No.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

The law of reflection states that the angle of incident and angle of reflected rays
A. are the same
B. are related to each other as nasinθa=nbsinθb
C. are related to each other as na/sinθa=nb/sinθb

A

A. are the same

20
Q 
When light passes through a material, its speed compared to the light velocity in
vacuum
A. Decreases
B. Increases
C. Does not change
A

A. Decreases

21
Q

Why when you put a stick into a glass of water it appears bended?
A. Because reflected rays from the stick refract at the surface water-air
B. Because the water acts as a converging lens
C. Because the light disperses when passing the surface water-air

A

A. Because reflected rays from the stick refract at the surface water-air

22
Q

Rays get reflected from a concave spherical mirror. Which of the rays is described incorrectly?
A. Ray passing via focal point reflects parallel to optical axis
B. Ray parallel to optical axis reflects passing via focal point
C. Ray parallel to optical axis reflects passing via the center of the sphere
D. Ray passing via the center of the sphere reflects via the center of the sphere

A

C. Ray parallel to optical axis reflects passing via the center of the sphere

23
Q

If light is reflected from a window, the reflected light
A.has no phase shift with respect to incident light
B.has a phase shift equal to π/2 with respect incident light C.has a phase shift equal to π with respect incident light D.has a phase shift equal to 3π/2 with respect incident light

A

Solution. Since window glass has its refraction index larger than the refraction index of the air, the light will reflect with phase shift equal to π. Answer C.

24
Q

Why do radio waves diffract around buildings, while light waves do not?
A. Radio waves travel much slower than light waves
B. Radio waves are electromagnetic waves while light waves are not. C. Radio waves have a much longer wavelengths than light waves.

A

Solution:
The wavelengths of AM radio waves are hundreds of meters, much larger than the size of buildings, so they easily diffract around buildings. Light, with wavelengths a tiny fraction of a centimeter, show no appreciable diffraction around buildings. Answer C.

25
Q

Which waves will likely experience interference when they pass between atomic planes in solids?
A. Radio waves
B. Lightwaves
C. X-rays

A

Solution. These must be X-rays because their wavelength is comparable with the distance between the atomic planes. Answer C.

26
Q

Diffraction gratings are used to determine
A. The velocity of light in the medium
B. The spectrum of light wavelengths emitted by a source
C. The distance between atoms in solids

A

Answer B.

27
Q 
An image formed by this thin divergent lens is
A. Virtual Erect 
B. Virtual Inverted 
C. Real Erect
D. Real Inverted
A

Virtual Erect

28
Q

If most materials shrink with decreasing temperature why upon freezing water pipes can blow up
A. It is connected to the positive thermal expansion coefficient of water around 0oC.
B. Itisconnectedtothezerothermalexpansioncoefficientofwateraround0oC.
C. It is connected to the negative thermal expansion coefficient of water around 0oC.

A

It is connected to the negative thermal expansion coefficient of water around 0oC.

29
Q 
An image of a coin embedded in the crystal ball is
A. Real Erect
B. RealInverted. 
C. VirtualErect.
D. Virtual Inverted.
A

C. VirtualErect.

30
Q

If you drive up the mountain with a bag of potato chips, you will find it inflated (or even burst open) because
A. The temperature on top of the mountain is smaller than the temperature of the chips
B. The temperature on top of the mountain is larger than the temperature of the chips
C. The pressure on top of the mountain is smaller than the pressure inside the bag
D. The pressure on top of the mountain is larger than the pressure inside the bag

A

C. The pressure on top of the mountain is smaller than the pressure inside the bag

31
Q

A ray parallel to the axis of a concave mirror

  1. Is reflected along the radius thru the center of the curvature of the mirror
  2. After reflection passes through the focal point
  3. Is reflected also parallel to the axis
A
  1. After reflection passes through the focal point
32
Q

A ray passing thru a focal point of a thin converging lens

  1. Is refracted parallel to the lens axis
  2. Does not deviate appreciably
  3. Refracts to pass through the second focal point
A
  1. Is refracted parallel to the lens axis
33
Q

An image of an object formed by this plane mirror is

  1. Virtual Erect
  2. Virtual Inverted
  3. Real Erect
  4. Real Inverted
A
  1. Virtual Erect
34
Q

A laser beam is directed onto two slits and the interference picture is seen on the screen behind it. The interference maxima occur when the path difference between the waves from each slit is equal to

  1. Integer number of wavelengths
  2. Odd integer number of wavelengths
  3. Odd integer number of half-wavelengths
A

1.Integer number of wavelengths

35
Q

A laser beam is directed onto two slits and the interference picture is seen on the screen behind it. The destructive interference occurs when the path difference between the waves from each slit is equal to

  1. Integer number of wavelengths
  2. Odd integer number of wavelengths
  3. Odd integer number of half-wavelengths
A

3.Odd integer number of half-wavelengths

36
Q

If light is passing through a window, the transmitted light 1.has no phase shift with respect to incident light

  1. has a phase shift equal to π/2 with respect incident light
  2. has a phase shift equal to π with respect incident light
  3. has a phase shift equal to 3π/2 with respect incident light
A

1.has no phase shift with respect to incident light

37
Q

The rainbow fringes seen on an oil drop in a glass of water are due to

  1. Interference between rays reflected from the top and bottom surfaces of the oil drop
  2. Interference between rays reflected from the top surface of the oil drop and the bottom of the glass
  3. Interference between rays reflected from the bottom surface of the oil drop and the bottom of the glass
A

1.Interference between rays reflected from the top and bottom surfaces of the oil drop

38
Q

A laser beam is directed onto a wide slit and the diffraction picture is seen on the screen behind it. The diffraction minima occur when the path difference between the waves from the slit is equal to

  1. Integer number of wavelengths
  2. Odd integer number of wavelengths
  3. Odd integer number of half-wavelengths
  4. There is no simple relationship
A

1.Integer number of wavelengths

39
Q

What is the difference between the Fraunhofer and Fresnel diffraction

  1. Fraunhofer diffraction considers rays that are approximately parallel (distant screen limit), Fresnel diffraction considers rays that are not parallel (the screen is close)
  2. Fraunhofer diffraction considers rays that are not parallel (the screen is close) , Fresnel diffraction considers rays that are approximately parallel (distant screen) 3.Fraunhofer diffraction considers wide slits, Fresnel diffraction considers narrow slits
  3. Fraunhofer diffraction considers narrow slits, Fresnel diffraction considers wide slits
A

1.Fraunhofer diffraction considers rays that are approximately parallel (distant screen limit), Fresnel diffraction considers rays that are not parallel (the screen is close)

40
Q

What is the typical wavelength of X-rays?

  1. a meter
  2. a millimeter
  3. a micrometer
  4. 10-10 m (Angstrom)
A

10-10 m (Angstrom)

41
Q

The Kelvin temperature scale is

  1. The same as the Fahrenheit scale with zero shifted to -273oF.
  2. The same as the Celsius scale with zero shifted to -273oC.
  3. Taken as the average of the Celsius and Fahrenheit scales.
A

2.The same as the Celsius scale with zero shifted to -273oC.

42
Q

Which statement is correct if any

  1. Two bodies in thermal equilibrium have the same temperatures
  2. Two bodies in thermal equilibrium have the same amount of heat
  3. Both statements are right.
  4. Both statements are wrong.
A

1.Two bodies in thermal equilibrium have the same temperatures

43
Q

To cool 1 liter of water from 10oC to 0oC you need to take out an amount of heat equal to Q=mcΔT=1419010 =41900 Joules. How much heat do you need to take out in order to transform the same water into ice at 0oC.

  1. 41900 Joules
  2. More than 41900 Joules
  3. Less than 41900 Joules
A
  1. More than 41900 Joules
44
Q

What is sublimation?

  1. Transformation from solid phase of matter to its liquid phase
  2. Transformation from liquid phase of matter to its gaseous phase
  3. Transformation from solid phase of matter to its gaseous phase by skipping the liquid (is it possible?)
A

3.Transformation from solid phase of matter to its gaseous phase by skipping the liquid (is it possible?)

45
Q

What are the mechanisms of the heat transfer? 1.Conduction

  1. Conduction, Convection and Radiation
  2. Conduction, Vaporization and Combustion
A

2.Conduction, Convection and Radiation

46
Q

A gas of particles is described by the van der Waals equation of state. Under which conditions do the van der Waals corrections become insignificant, i.e. the gas can be described by the ideal gas equation of state?

  1. In the limit of high temperatures
  2. In the limit of small temperatures
  3. In the limit of high densities
  4. In the limit of low densities
A

In the limit of low densities

PHY 9B (3 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions