Waves

Ranges of waves which overlap are

A. x-rays and gamma rays

B. x-rays and infrared rays

C. gamma rays and infrared rays

D. UV rays and infrared rays

At points in a sound wave where the gas is maximally compressed, the pressure 

A. is a maximum 

B. is a minimum 

C. is equal to the ambient value 

D. is greater than the ambient value but less than the maximum 

E. is less than the ambient value but greater than the minimum

“Beats” in sound refer to: 

A. interference of two waves of the same frequency 

B. combination of two waves of slightly different frequency 

C. reversal of phase of reflected wave relative to incident wave 

D. two media having slightly different sound velocities 

E. effect of relative motion of source and observer

Longitudinal waves gives rise to

A. amplitude

B. frequency

C. wavelength

D. high and low pressure regions

To raise the pitch of a certain piano string, the piano tuner: 

A. loosens the string 

B. tightens the string 

C. shortens the string 

D. lengthens the string 

E. removes some mass

Changing magnetic field induces 

A. charge 

B. current 

C. frequency 

D. voltage 

Frequency and time period are

A. directly related

B. not related

C. inversely related

D. directly proportional

A sinusoidal wave is generated by moving the end of a string up and down periodically. The generator does not supply any power when the end of the string 

A. has its least acceleration 

B. has its greatest displacement 

C. has half its greatest displacement 

D. has one-fourth its greatest displacement 

E. has its least displacement

When a 100-Hz oscillator is used to generate a sinusoidal wave on a certain string the wavelength is 10 cm. When the tension in the string is doubled the generator produces a wave with a frequency and wavelength of: 

A. 200 Hz and 20 cm 

B. 141 Hz and 10 cm 

C. 100 Hz and 20 cm 

D. 100 Hz and 14 cm 

E. 50 Hz and 14 cm

If the length of a piano wire (of given density) is increased by 5%, what approximate change in tension is necessary to keep its fundamental frequency unchanged? 

A. Decrease of 10% 

B. Decrease of 5% 

C. Increase of 5% 

D. Increase of 10% 

E. Increase of 20%