Sound

The instrument that measures atmospheric pressure is

pH value of pure water is -

Refers to a pulse transmitter-receiver used in radio navigation and secondary surveillance radar to either a reply from transponder is called

Which primary colours produce different shades on TV screen?

The scanning of uterus in determining the sex of the child is preferred more with ultrasonic waves rather than with X-rays. It is because.

Which type of waves are used by a 'RADAR' for detecting the presence of an aircraft?

Bose speaker produces a sound during the concert which has $120$ crests and $120$ troughs in $0.6$ seconds. What is the frequency of the wave$?$

The sound of an aircraft roughly corresponds to -

Which of the following statements is INCORRECT?

What is the effect on apparent frequency when the distance between the source of the sound and listener is decreased?

Transverse waves cannot travel through

A person clapped his hands near a cliff and heard the echo after $4 \mathrm{s}$. The distance between the cliff and the person will be :

(Speed of sound is $346 \mathrm{m} {\mathrm{s}}^{-1}$) 

Waves inside a gas are

If the velocity of sound in air is $340 \mathrm{m} {\mathrm{s}}^{-1}$ and $x$ is the minimum distance between sound source and reflecting surface to get echo from general sound, then :

Which of the following statements is correct?

What is the rate at which a wave moves through water and is measured in knots?

For a wave, wavelength divided by the time period is equal to_____.

Speeds greater than the speed of sound in the air are known as _____.

Which of the following is the correct relation for mach number?

What is the mach number of an circuit flying with a speed of $450 \raisebox{1ex}{$\mathrm{m}$}\!\left/ \!\raisebox{-1ex}{$\mathrm{s}$}\right.$ at a temperature of $290\mathrm{K}$?