21.
Which is a correct way to measure wavelength?

22.
If the phase difference between two points is 120° for a wave with velocity of 360 m/s and frequency 500 Hz, then path difference between the two points is

23.
Why are we able to hear short wave broadcasts better than long wave broadcasts ?

24.
The frequency of ultrasound wave is typically

25.
Which of the following has the highest frequency?

28.
Intensity of any wave is proportional to which of the following?

29.
If density of oxygen is 16 times that of hydrogen, what will be their corresponding ratio of velocity of sound?

30.
Which one of the following statements with regard to Jet stream, an upper level tropospheric wave, is not correct?