CBSE
Two vibrating strings of the same material but lengths L and 2L have radii 2r and r respectively. They are stretched under the same tension. Both the strings vibrate in their fundamental modes, the one of length L with frequency and the other with frequency The ratio is
2
4
8
1
An engine moving towards a wall with a velocity 50 m/s emits a note of 1.2 kHz. Speed of sound in air is 350 m/s. The frequency of the note after reflection from the wall as heard by the driver of the engine is
2.4 kHz
0.24 kHz
1.6 KHz
1.2 kHz
A closed organ pipe of length 20 cm is sounded with tuning fork in resonance. What is frequency of tuning fork? (v = 332 m/s)
300 Hz
350 Hz
375 Hz
415 Hz
A tuning fork A produces 4 beats/s with another tuning fork B of frequency 320 Hz. On filing one of the prongs of A, 4 beats/s are again heard when sounded with the same fork B. Then, the frequency of the fork A before filing is
328 Hz
316 Hz
324 Hz
320 Hz
The sound waves after being converted into electrical waves are not transmitted as such because
they travel with the speed of sound
the frequency is not constant
they are heavily absorbed by the atmosphere
the height of antenna has to be increased several times
A transverse wave is expressed as, For what value of λ, maximum particle velocity equals to 4 times the wave velocity?
When sound waves travel from air to water which one of the following remains constant?
Time period
Frequency
Velocity
Wavelength
Which one of the following statements is true?
Both light and sound waves in air are transverse
The sound waves in air are longitudinal while the light waves are transverse
Both light and sound waves in air are longitudinal
Both light and sound waves can travel in vacuum
A closed organ pipe of length 20 cm is sounded with tuning fork in resonance. What is the frequency of tuning fork? (v = 332 m/s)
300 Hz
350 Hz
375 Hz
415 Hz
y = 3 sin represents an equation of a progressive wave, where t is in second and x is in metre. The distance travelled by the wave in 5 s is
8 m
10 m
5 m
32 m