Question 1

A string under tension carries a transverse wave traveling at speed v.If the linear density of the string is halved,what is the wave speed?

Accepted Answer

A) The wave speed is unchanged. 
B) The wave speed is halved. 
C) The wave speed is quadrupled. 
D) The wave speed decreases to about 71% of v. 
E) The wave speed increases by about 41%. 
A) The wave speed is unchanged. 
B) The wave speed is halved. 
C) The wave speed is quadrupled. 
D) The wave speed decreases to about 71% of v. 
E) The wave speed increases by about 41%.

Question 2

A sound pulsar unit puts out short sound bursts at constant time intervals.This unit also has a receiver to listen to the time delay from an echo from any objects or walls.If the unit is positioned such that the echo time corresponds to the sound burst interval of 0.6 s,find the distance to the reflecting wall.(velocity of sound in air = 331 m/s)

Accepted Answer

A) 150 m 
B) 50.0 m 
C) 200 m 
D) 100 m 
E) none of the above 
A) 150 m 
B) 50.0 m 
C) 200 m 
D) 100 m 
E) none of the above

Question 3

If you were to reduce the amplitude of a wave on a string by half while keeping the speed and frequency of the wave constant,the energy delivered by the wave would

Accepted Answer

A) double. 
B) quadruple. 
C) be reduced 50%. 
D) be reduced to 25% of its previous value. 
E) be unchanged. 
A) double. 
B) quadruple. 
C) be reduced 50%. 
D) be reduced to 25% of its previous value. 
E) be unchanged.

Question 4

You are in a park when you spot your friend 100 m away.At what lowest decibel should you shout your greetings so that your friend can just hear you? Assume that your friend has normal hearing.

Accepted Answer

A) 30 dB 
B) 40 dB 
C) 50 dB 
D) 60dB 
E) 70 dB 
A) 30 dB 
B) 40 dB 
C) 50 dB 
D) 60dB 
E) 70 dB

Question 5

A siren of frequency 3.20 kHz moves away from a stationary observer with a speed of 30.5 m/s.If the speed of sound is 335 m/s,the frequency heard by the observer is

Accepted Answer

A) 2.66 kHz 
B) 2.93 kHz 
C) 3.49 kHz 
D) 3.52 kHz 
E) 3.84 kHz 
A) 2.66 kHz 
B) 2.93 kHz 
C) 3.49 kHz 
D) 3.52 kHz 
E) 3.84 kHz

Question 6

At an outdoor bandstand,what would be the difference in the sound intensity level (dB)received by a listener 5 m from the bandstand and a listener 40 m from the bandstand,assuming there is no sound reflection? [$\beta$ = 10 log(I/I0)]

Accepted Answer

A) 8 dB 
B) 9 dB 
C) 10 dB 
D) 18 dB 
E) The answer depends on how loudly the band plays. 
A) 8 dB 
B) 9 dB 
C) 10 dB 
D) 18 dB 
E) The answer depends on how loudly the band plays.

Question 7

. A whistle is whirled around in a horizontal circle 120 times a minute at the end of a piece of string 1.5 m in length.If the standard frequency of the whistle is 550 Hz,calculate the difference between the highest and lowest frequencies heard by a stationary observer (assume the speed of sound in air = 343 m/s).

Accepted Answer

A) 58 Hz 
B) 64 Hz 
C) 61 Hz 
D) 32 Hz 
E) 29 Hz 
A) 58 Hz 
B) 64 Hz 
C) 61 Hz 
D) 32 Hz 
E) 29 Hz

Question 8

Use the following scenario to answer the next question. A rope of length L and linear mass density $\mu$ is tied to the ceiling on one end. The other end is tied to a spring with spring constant k,and the spring is then attached to the floor,extending it by A.
-The tension of the rope at height y from the spring is

Accepted Answer

A) kA 
B) $\mu$gy 
C) $\mu$gy + kA 
D) $\mu$gy - kA 
E) kA - $\mu$gy 
A) kA 
B) $\mu$gy 
C) $\mu$gy + kA 
D) $\mu$gy - kA 
E) kA - $\mu$gy

Question 9

Two sounds differ by 20 dB.This means that the louder sound is _____ times as intense and _____ times as loud.

Accepted Answer

A) twenty; twenty 
B) one hundred; twenty 
C) twenty; four 
D) one hundred; four 
E) two; two 
A) twenty; twenty 
B) one hundred; twenty 
C) twenty; four 
D) one hundred; four 
E) two; two

Question 10

You have a rope that is 10 m long and has a mass of 0.2 kg.In addition,you have an oscillator that can generate a 5 Hz wave with an amplitude of 10 cm.What should the tension in the rope be if you need to transmit 10 W of power along the rope?

Accepted Answer

A) 102 N 
B) 205 N 
C) 320 N 
D) 51 N 
E) 250 N 
A) 102 N 
B) 205 N 
C) 320 N 
D) 51 N 
E) 250 N

Question 11

A particle is subject to a wave motion.Its distance from the equilibrium position at any particular time is called its

Accepted Answer

A) amplitude 
B) displacement 
C) phase 
D) wavelength 
E) period 
A) amplitude 
B) displacement 
C) phase 
D) wavelength 
E) period

Question 12

The equation that gives the particle displacement of a medium in which there is a simple harmonic progressive wave is   where the units are SI.At t = 2 s,the velocity of a particle at x = 10 m is

Accepted Answer

A) 0 
B) 2 m/s 
C) 4/$\pi$ m/s 
D) 4 m/s 
E) 8 m/s 
A) 0 
B) 2 m/s 
C) 4/$\pi$ m/s 
D) 4 m/s 
E) 8 m/s

Question 13

The angle of the shock wave produced by a jet traveling at Mach 3 at an altitude of 4000 m (assume the speed of sound to be 340 m/s at this altitude)is approximately

Accepted Answer

A) 10º 
B) 13º 
C) 19º 
D) 20º 
E) 38º 
A) 10º 
B) 13º 
C) 19º 
D) 20º 
E) 38º

Question 14

The equation of a transverse wave is   where the units are SI.The velocity of the wave is

Accepted Answer

A) 0.20$\pi$ m/s 
B) 8$\pi$ m/s 
C) 40 m/s 
D) 0.20 km/s 
E) 0.40$\pi$ km/s 
A) 0.20$\pi$ m/s 
B) 8$\pi$ m/s 
C) 40 m/s 
D) 0.20 km/s 
E) 0.40$\pi$ km/s

Question 15

Suppose the apparent wavelength of the known lines in the spectrum of hydrogen are measured to increase by 50% when light from a distant galaxy is observed on Earth (this is known as the Red Shift).Calculate the speed of recession of the galaxy relative to Earth as a percentage of the speed of light.

Accepted Answer

A) 50% 
B) 20% 
C) 38% 
D) 63% 
E) 60% 
A) 50% 
B) 20% 
C) 38% 
D) 63% 
E) 60%

Question 16

Electromagnetic waves

Accepted Answer

A) include light,radio waves,X rays,gamma rays,and microwaves. 
B) do not require a medium for propagation. 
C) travel through a vacuum with a speed of approximately 3 $\times$108 m/s. 
D) are produced when free electrons accelerate. 
E) are described by all of the above 
A) include light,radio waves,X rays,gamma rays,and microwaves. 
B) do not require a medium for propagation. 
C) travel through a vacuum with a speed of approximately 3 $\times$108 m/s. 
D) are produced when free electrons accelerate. 
E) are described by all of the above

Question 17

A traveling wave passes a point of observation.At this point,the time between successive crests is 0.2 s.Which of the following statements can be justified?

Accepted Answer

A) The wavelength is 5 m. 
B) The frequency is 5 Hz. 
C) The velocity of propagation is 5 m/s. 
D) The wavelength is 0.2 m. 
E) There is not enough information to justify any of these statements. 
A) The wavelength is 5 m. 
B) The frequency is 5 Hz. 
C) The velocity of propagation is 5 m/s. 
D) The wavelength is 0.2 m. 
E) There is not enough information to justify any of these statements.

Question 18

Two waveforms of the same frequency are moving to the right.The power PA transmitted by wave A is equal to

Accepted Answer

A) 2PB/3 
B) 9PB/4 
C)    PB        
D) 4PB/9 
E) PB  
A) 2PB/3 
B) 9PB/4 
C)    PB        
D) 4PB/9 
E) PB

Question 19

If you were to quadruple the speed of a wave on a string while keeping the frequency and amplitude of the wave constant,the rate at which energy is delivered by the wave would

Accepted Answer

A) double. 
B) quadruple. 
C) be reduced 50%. 
D) be reduced to 25% of its previous value. 
E) be unchanged. 
A) double. 
B) quadruple. 
C) be reduced 50%. 
D) be reduced to 25% of its previous value. 
E) be unchanged.

Question 20

Which of the following statements is true?

Accepted Answer

A) Waves transmit energy but not momentum. 
B) Waves transmit momentum but not energy. 
C) Waves transmit both energy and momentum. 
D) Waves transmit neither energy nor momentum. 
E) Waves can transmit either energy or momentum but not both. 
A) Waves transmit energy but not momentum. 
B) Waves transmit momentum but not energy. 
C) Waves transmit both energy and momentum. 
D) Waves transmit neither energy nor momentum. 
E) Waves can transmit either energy or momentum but not both.

Exam 15: Wave Motion

A string under tension carries a transverse wave traveling at speed v.If the linear density of the string is halved,what is the wave speed?

If you were to reduce the amplitude of a wave on a string by half while keeping the speed and frequency of the wave constant,the energy delivered by the wave would

You are in a park when you spot your friend 100 m away.At what lowest decibel should you shout your greetings so that your friend can just hear you? Assume that your friend has normal hearing.

A siren of frequency 3.20 kHz moves away from a stationary observer with a speed of 30.5 m/s.If the speed of sound is 335 m/s,the frequency heard by the observer is

At an outdoor bandstand,what would be the difference in the sound intensity level (dB)received by a listener 5 m from the bandstand and a listener 40 m from the bandstand,assuming there is no sound reflection? [ β\betaβ = 10 log(I/I0)]

Two sounds differ by 20 dB.This means that the louder sound is _____ times as intense and _____ times as loud.

You have a rope that is 10 m long and has a mass of 0.2 kg.In addition,you have an oscillator that can generate a 5 Hz wave with an amplitude of 10 cm.What should the tension in the rope be if you need to transmit 10 W of power along the rope?

A particle is subject to a wave motion.Its distance from the equilibrium position at any particular time is called its

The equation that gives the particle displacement of a medium in which there is a simple harmonic progressive wave is where the units are SI.At t = 2 s,the velocity of a particle at x = 10 m is

The angle of the shock wave produced by a jet traveling at Mach 3 at an altitude of 4000 m (assume the speed of sound to be 340 m/s at this altitude)is approximately

The equation of a transverse wave is where the units are SI.The velocity of the wave is

Electromagnetic waves

A traveling wave passes a point of observation.At this point,the time between successive crests is 0.2 s.Which of the following statements can be justified?

Two waveforms of the same frequency are moving to the right.The power PA transmitted by wave A is equal to

If you were to quadruple the speed of a wave on a string while keeping the frequency and amplitude of the wave constant,the rate at which energy is delivered by the wave would

Which of the following statements is true?

Systems of Measurement

Motion in One Dimension

Motion in Two and Three Dimensions

Newtons Laws

Applications of Newtons Laws

Work and Energy

Conservation of Energy

Systems of Particles and Conservation of Linear Momentum

Rotation

Conservation of Angular Momentum

Gravity

Static Equilibrium and Elasticity

Fluids

Oscillations

Superposition and Standing Waves

Temperature and the Kinetic Theory of Gases

Heat and the First Law of Thermodynamics

The Second Law of Thermodynamics

Thermal Properties and Processes

The Electric Field I: Discrete Charge Distributions

The Electric Field Ii: Continuous Charge Distributions

Electric Potential

Capacitance

Electric Current and Direct-Current Circuits

The Magnetic Field

Sources of the Magnetic Field

Magnetic Induction

Alternating-Current Circuits

Maxwells Equations and Electromagnetic Waves

Properties of Light

Optical Images

Interference and Diffraction

Wave Particle Duality and Quantum Physics

Applications of the Schrodinger Equation

Atoms

Molecules

Solids and the Theory of Conduction

Relativity

Nuclear Physics

Elementary Particles and the Beginning of the Universe

Filters

At an outdoor bandstand,what would be the difference in the sound intensity level (dB)received by a listener 5 m from the bandstand and a listener 40 m from the bandstand,assuming there is no sound reflection? [ $\beta$ = 10 log(I/I₀)]

Two sounds differ by 20 dB.This means that the louder sound is _ times as intense and _ times as loud.

Two waveforms of the same frequency are moving to the right.The power P_A transmitted by wave A is equal to