Calculating Up-Doppler with 600nm Laser Scanning at 55m/s | Mega Sig Figs

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To calculate the up-Doppler shift for a 600 nm laser scanning a motorcycle traveling at 55 m/s, the speed of light, rather than sound, should be used due to the nature of electromagnetic waves. The Doppler effect applies to various types of waves, including sound and light, and is influenced by the motion of the source and receiver. In this scenario, the motorcycle is the moving source while the police car remains stationary. The frequency observed by the motorcyclist can be calculated using the formula f = (c + v) / λ, where c is the speed of light and v is the motorcycle's speed. Understanding the relationship between wave properties and motion is crucial for accurate calculations in this context.
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Okay, I don't need an answer . . . I just need to know how I would go about getting an answer.

Here is the question, exactly worded as on my worksheet:

"What is the up-doppler for a 600.0 nanometer laser scanning an innocent, law-abiding, safe-driving, tax-paying, completely innocent, God-fearing, innocent, motorcyclist closing this barely legal speed trap at a reasonable for conditions 198.00 km/hr? Use mega sig figs."

I converted km/hr into m/s and got 55 m/s for the speed of the motorcycle. Now, for the up-doppler, would I take the 600 nanometer and multiply it by the velocity of sound over the quantity (velocity sound + velocity of source)?

I am really confused.
 
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For electromagnet or optical sources the speed of sound is inmaterial. You would use the speed of light.
 
I don't understand that though . . . we are doing the unit on sound, so how would the speed of light be applicable?
 
Light travels as a wave, similar to sound.
You're doing a chapter on WAVES.
The Doppler effect occurs for water waves and string waves, too.
For most waves, it is important whether the SOURCE is moving, or whether the RECEIVER is moving.
In your case, the motorcycle is moving, the police car is not.
The motorcyclist receives waves of lambda, at a rate f = (c+v)/lambda.
If you want to treat the REFLECTED waves (as the police want to do),
the waves that the motorcyclist emits have lambda_back = (c+v)/f .
 

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