Given below are two statements :
Statement I : For transmitting a signal, size of antenna ( $f$ ) should be comparable to wavelength of signal (at least $l=\frac{\lambda}{4}$ in dimension)
Statement II : In amplitude modulation, amplitude of carrier wave remains constant (unchanged)
In the light of the above statements, choose the most appropriate answer from the options given below,
Given below are two statements :
Statement I : For transmitting a signal, size of antenna ( $f$ ) should be comparable to wavelength of signal (at least $l=\frac{\lambda}{4}$ in dimension)
Statement II : In amplitude modulation, amplitude of carrier wave remains constant (unchanged)
In the light of the above statements, choose the most appropriate answer from the options given below,
Show Hint
- Statement I is correct but Statement II is incorrect
- Both Statement I and Statement II are incorrect
- Both Statement I and Statement II are correct
- Statement I is incorrect but Statement II is correct
The Correct Option is A
Solution and Explanation
Statement I: The size of the antenna for efficient signal transmission should be comparable to the wavelength of the signal. Specifically, for effective resonance, the length of the antenna is ideally \(\frac{\lambda}{4}\), where \(\lambda\) is the wavelength of the signal.
Hence, Statement I is correct.
Statement II: In amplitude modulation (AM), the amplitude of the carrier wave changes depending on the information signal, while the frequency and phase remain constant. Therefore, Statement II is incorrect.
Thus, the correct answer is that Statement I is correct, while Statement II is incorrect.
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Concepts Used:
Waves
Waves are a disturbance through which the energy travels from one point to another. Most acquainted are surface waves that tour on the water, but sound, mild, and the movement of subatomic particles all exhibit wavelike properties. inside the most effective waves, the disturbance oscillates periodically (see periodic movement) with a set frequency and wavelength.
Types of Waves:
Transverse Waves -
Waves in which the medium moves at right angles to the direction of the wave.
Examples of transverse waves:
- Water waves (ripples of gravity waves, not sound through water)
- Light waves
- S-wave earthquake waves
- Stringed instruments
- Torsion wave
The high point of a transverse wave is a crest. The low part is a trough.
Longitudinal Wave -
A longitudinal wave has the movement of the particles in the medium in the same dimension as the direction of movement of the wave.
Examples of longitudinal waves:
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