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mustang
Mar1-04, 01:08 PM
Problem 17.
The speed of all elctromagnetic waves in empty space is 3*10^8 m/s.
What is the wavelength of X rays emitted at 3.2*10^12 MHz? Answer in m.
This is what I have done;
wavespeed=frequence times wavelength
3*10^8/3.2*10^12 = 9.375 * 10 ^-5 m
I got this answer for the problem but when I submitted the answer it was wrong, what did I do wrong?

Doc Al
Mar1-04, 01:44 PM
The frequency was given in MHz; you need to convert to Hz. 1 MHz = 10^6 Hz.

mustang
Mar1-04, 08:50 PM
Would it then be 3.2*10^12MHz * 10^6Hz=3.2*10^19 Hz

himanshu121
Mar1-04, 10:21 PM
Originally posted by mustang
Would it then be 3.2*10^12MHz * 10^6Hz=3.2*10^19 Hz

12 + 6 = ?????

mustang
Mar1-04, 10:49 PM
So himanshu121 it would really be 3.2*18. Since you pointed out 12+6=18?

himanshu121
Mar2-04, 12:06 AM
Dear it is 3.2 * 1018 Hz now apply the formula u will get it

mustang
Mar2-04, 08:06 AM
So by dividing 3*10^8 by 3.2*10^18 = 9.375*10^-11 is the answer?

Doc Al
Mar2-04, 08:12 AM
Originally posted by mustang
So by dividing 3*10^8 by 3.2*10^18 = 9.375*10^-11 is the answer?
Yep. Your original answer was off by a million, since you used the wrong units for frequency.