Can the Doppler Effect Cause Changes in Radio Wave Frequency?

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SUMMARY

The Doppler effect causes a change in wavelength and frequency for all types of waves, including radio waves. In the discussion, a radio station transmits at 90 kHz, and as a car accelerates towards the station at 108 km/h, the frequency received by the antenna shifts slightly to 90,000.009 Hz when approaching and 89,999.991 Hz when moving away. This minimal frequency shift occurs because the speed of the car is negligible compared to the speed of radio waves, resulting in an imperceptible change in energy loss.

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  • Understanding of the Doppler effect
  • Basic knowledge of wave frequency and wavelength
  • Familiarity with radio wave propagation
  • Concept of relative motion in physics
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shihab-kol
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I have learned that the Doppler effect causes a change in wavelength (and thus frequency) in all types of waves
Suppose there is a radio station transmitting waves of frequency 90 kHz and the antennae in my car is tuned to that frequency.
Then I start to accelerate and thus I am changing my position relative to the station .
Then due to Doppler effect the waves would have to travel a longer distance and thus there has to be a change in frequency of the waves due to energy loss.
But I can still hear the radio at that frequency , why does this happen?
 
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[edit] Hello shihab, :welcome: !

This happens because your radio may be tuned to 90 kHz exactly , but it also perfectly receives the 90000.009 HZ the antenna picks up when you are driving towards the sender at 108 km/h, or the 89999.991 Hz when you drive away from it.

In short: because your speed / wave propagation speed is so small (like 30/300000000 in this example)
 
So you mean to say that
BvU said:
[edit] Hello shihab, :welcome: !

This happens because your radio may be tuned to 90 kHz exactly , but it also perfectly receives the 90000.009 HZ the antenna picks up when you are driving towards the sender at 108 km/h, or the 89999.991 Hz when you drive away from it.

In short: because your speed / wave propagation speed is so small (like 30/300000000 in this example)
So, you mean to say that as my speed or velocity is very small compared to that of the radio waves that is why the frequency does not change by a huge amount ?
Is the loss in energy small?
Thanks
 
shihab-kol said:
So, you mean to say that as my speed or velocity is very small compared to that of the radio waves that is why the frequency does not change by a huge amount ?
Correct. 0.009 Hz really is a very small amount :smile: of shift for a radio wave.
shihab-kol said:
Is the loss in energy small?
What loss in energy ?
 
BvU said:
Correct. 0.009 Hz really is a very small amount :smile: of shift for a radio wave.
What loss in energy ?
Okay, I now understand .
Thank You.:smile:
 

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