A car sounding a horn of frequency 100 Hz passes an observer. The ratio of frequencies of the horn noted by the observer, before and after passing of car is 11:9. if the speed of […]
What should be the velocity(v) of a sound source moving towards a stationary observer so that apparent frequency is double the actual frequency
Options
(a) v (b) 2v (c) v/2 (d) v/4
Correct […]
A string in musical instrument is 50 cm long and its fundamental frequency is 800 Hz. If a frequency of 1000 Hz is to be produced, then required length of string is
Options
Length of a string tied to two rigid supports is 40 cm. Maximum length (wavelength in cm) of a stationary wave produced in it is
Options
(a) 20 cm (b) 80 cm (c) […]
The tension in a piano wire is 10 N. What should be the tension in the wire to produce a note of double the frequency?
Options
(a) 5 N (b) 20 N (c) […]
If the velocity of sound in air is 350 m/s, then the fundamental frequency of an open organ pipe of length 50 cm will be
Options
(a) 350 Hz (b) 175 Hz (c) […]
When we hear a sound, we can identify its source from
Options
(a) Amplitude of sound (b) Intensity of sound (c) Wavelength of sound (d) Overtones present in the sound
Correct Answer:
Overtones present […]
Which of the following is not a transverse wave?
Options
(a) X-rays (b) γ-rays (c) Visible light waves (d) Sound waves in a gas
Correct Answer:
Sound waves in a gas
Explanation:
No […]
Two sources P and Q produce notes of frequency 660 Hz each. A listener moves from P to Q with a speed of 1 ms⁻¹. If the speed of sound is 330 m/s, then the […]
A wave travelling in the +ve x-direction having displacement along y-direction as 1m, wavelength 2π and frequency 1 /π Hz is represented by
Options
(a) y = sin ( 2 πx – 2 […]
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