A 60.0 kHz transmitter sends an EM wave to a receiver 21 km away. The ...
Explanation:
When an electromagnetic wave is reflected from a surface, the phase of the wave changes by 180 degrees. In this situation, the signal from the transmitter is being reflected by a helicopter and then reaching the receiver. When the original signal and the reflected signal reach the receiver, they may interfere with each other. The interference can be constructive, destructive, or something in between, depending on the phase difference between the two signals.
Destructive Interference:
In this case, the two signals will be out of phase by 180 degrees because of the reflection from the helicopter. The crest of one wave will coincide with the trough of the other wave, resulting in a cancellation of the waves. This will lead to a decrease in the amplitude of the resultant wave, which means that the signal received by the receiver will be weaker than the original signal sent by the transmitter. Hence, the correct answer is option 'B', destructive interference.
Conclusion:
The phenomenon of interference is an important aspect of wave propagation. It can be constructive, destructive, or something in between, depending on the phase difference between the waves. In this case, the reflection from the helicopter causes a phase shift of 180 degrees, resulting in destructive interference. This means that the signal received by the receiver will be weaker than the original signal sent by the transmitter.
A 60.0 kHz transmitter sends an EM wave to a receiver 21 km away. The ...
How it is destructive interference.???