Bats detect the obstacles in their path by receiving the reflected
Infrasonic waves .
Ultrasonic waves.
Electromagnetic waves.
Radio waves .
A wave completes 24 cycles in 0.8 s. The frequency of the wave is
30 Hz
8 Hz
24 Hz
12 Hz
Which quantity out of the following determines the loudness of a sound wave?
Wavelength.
Frequency .
Amplitude .
None of these .
A wire stretched between two fixed supports, is plucked exactly in the middle and then released. It executes
Resonant vibration with decreasing amplitude.
Free vibrations .
Damped vibration .
Forced vibration .
The distance between two consecutive crests is L, then the wavelength is given by
L/2
2 L
4 L
L
If the frequency of a wave is doubled, its wavelength
becomes doubled
remains same
is halved
none of these
Vibrations, whose amplitude of oscillations decreases with time are called
free vibrations
forced vibrations
damped vibrations
The unit used to measure the sound level is
phon
decibel
watt
Hertz
A periodic wave is characterized by
phase only
wavelength only
frequency only
all the above
A certain sound has a frequency of 256 Hz and a wave length of 1.3 m. Calculate the speed with which this sound travels :
33.28 ms-1.
3.328 ms-1.
332.8 ms-1.
333.8 ms-1.