Calculating the Speed of an Electromagnetic Wave: Basic Physics Question

AI Thread Summary
An electromagnetic wave with a frequency of 7.8x10-10 Hz is being analyzed for its speed. The formula C=λv is relevant, where C represents the speed of light, λ is the wavelength, and v is the frequency. It is confirmed that all electromagnetic waves travel at the speed of light in a vacuum, approximately 3x10^8 m/s. Therefore, the problem is not a trick question; the speed of the wave is indeed the speed of light. Understanding this principle is essential in physics.
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Basic physics question?

Homework Statement


My younger sister has a problem stated:

"An electromagnetic wave is found to have a frequency of 7.8x10-10 Hz. What is the speed of the wave?"


Homework Equations





The Attempt at a Solution



It's been a while since I have done this, and I'm a little confused. I know that you typically use the formula: C=λv (C= speed of light, λ= wavelength, v=frequency). I'm not sure, but I was thinking maybe it's a trick question, because I thought electromagnetic waves all travel at the speed of light (~3x108 m/s). Am I correct in assuming this?

Any help is appreciated.

Thanks.
 
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Yes, I think you are right, it is a trick question, since the speed of light in vacuum is always ~3x108m/s
 

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