Electromagnetic Radiation-Really easy but I am stuck

AI Thread Summary
The discussion revolves around calculating the number of wavelengths of electromagnetic radiation emitted by a 60 Hz electrical transmission line needed to cover a distance of 5,000 km. The user initially attempts to use the formula v = fλ, calculating the wavelength as 5.0 x 10^6 meters, which they believe is incorrect. Other participants emphasize the importance of unit conversion and suggest that the initial calculation isn't as far off as perceived. The correct approach involves understanding the relationship between speed, frequency, and wavelength in the context of electromagnetic radiation. Ultimately, clarity on units and calculations is crucial for arriving at the right answer.
samdiah
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Homework Statement



How many wavelengths of radiation emitted by a 60 Hz electrical transmission line would it take to span the North American continent (a distance approximation 5.0*10^3 km).

f=60Hz
d=5.0*0^3 km=5.0*10^6 m

Homework Equations



v=fλ
Δd=vΔt

The Attempt at a Solution



Δt=d/v
= 1.67*10^-2

If speed is c then wavelength should equal c/f=3.0*10^8/60
=5.0*10^6

Which is absoloutely wrong since answer is 1.0.

Please help me and thanks in advance.
 
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samdiah said:
Δt=d/v
= 1.67*10^-2
Not sure what you are calculating here.

If speed is c then wavelength should equal c/f=3.0*10^8/60
=5.0*10^6
That's all you need. Hint: Units!

Which is absoloutely wrong since answer is 1.0.
Not as wrong as you think! :wink:
 
Thank You very much!
 

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