Question

Figure 24.26 shows the interference pattern of two radio antennas broadcasting the same signal. Explain how this is analogous to the interference pattern for sound produced by two speakers. Could this be used to make a directional antenna system that broadcasts preferentially in certain directions? Explain

Short answer

Interference cannot be avoided in order to create an aerial system that broadcasts in specific directions.

Step-by-step solution

Definition of Radio antenna

Radio antenna: An antenna, also known as an aerial, is a device that connects radio waves traveling through space with electric currents flowing through metal conductors.

Explanation of answer

The propagation of the acoustic wave is longitudinal. Hence, they produce compression and rarefaction within the air. The sound waves emitting from the 2 speakers interact in any respect points around them. at most of the points, undulation from one speaker causes rarefaction, and also the wave from other speaker causes compression.

Hence, this leads to destructive interference.

Explaining further

At some points, both waves either cause rarefaction or compression. This leads to constructive interference. The solid dots show constructive interference. The energy of those waves is above destructive interference.

It is clear from the figure that constructive interference occurs in many directions.

Therefore, interference can't be wont to make an aerial system that broadcasts preferentially in certain directions.