Question

The radio waves of frequency $30MHz$ to $300MHz$ belong to:
(A) high frequency band
(B) very high frequency band
(C) ultra high frequency band
(D) super high frequency band

Answer 1

Hint
To solve this problem we just need to have a basic idea of the range up to which the high-frequency range, the very high-frequency range, the ultra-high-frequency range, and the super-high frequency range extend up to. In the question given, we need to see in which band $30 - 300MHz$this range of frequency falls under.

Complete Step by Step Solution
To solve this we need to know first what radio waves are. So radio waves are electromagnetic waves which have a wavelength longer than the infrared light and lie on the electromagnetic spectrum. The radio waves themselves span upon a huge range of frequencies, starting as low as $30Hz$up to as high as $300GHz$. In our question, the options are given for four frequency bands.
So we need to find the range of frequency of these four bands.
The high frequency band has a frequency range from $3MHz$ to $30MHz$
The very high frequency band ranges from $30MHz$ to $300MHz$.
The ultra high frequency band ranges from $300MHz$to $1000MHz$.
And the super high frequency band has a frequency range of $2GHz$to $4GHz$.
Thus from these ranges, we can say that the range of frequency given in the question, that is, $30MHz$ to $300MHz$belongs to the very high-frequency range.
So the correct option is (B).

Additional Information
For any wave, its wavelength is inversely proportional to its wavelength. So as the frequency increases, the wavelength decreases. The wavelength range of the four bands given in the question is,
High-frequency band - $100m$ to $10m$
Very high frequency band - $10m$ to $1m$
Ultra-high frequency band - $1m$ to $30cm$
Super high frequency band - $30cm$ to $15cm$.

Note
Radio waves have a huge number of uses in our surroundings. The radio wave communication signals travel through the air in a straight line and are mainly used for broadcasting in radio and televisions. A few very common uses of the very high frequency band of the radio waves are, the digital audio broadcasting (DAB), the FM broadcasting, low range data communication with radio modems, etc.