- #1

Salerk

- 9

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## Homework Statement

An FM radio station generates radio waves that have a frequency of 95.5 MHz. The frequency of the waves from a competing station have a frequency of 102.7 MHz. What is the difference in wavelength between the waves emitted from the two stations?

f1= 95.5

f2=102.7

## Homework Equations

From what I know

Speed = Frequency x wavelength (v=fλ)

I need to find out wavelength 2 - wavelength 1. This i understand no problem thing that's got me is the equation the tutor gave to work out the equation is...

λ2-λ1=v/f2 - v/f2 <-- Why would I be subtracting the same from the same the answer would be = to zero, would the equation not be...

λ2-λ1=v/f2 - v/f1

I love my physics classes but sadly our tutor 80% of the time runs out of time before he finishes the class but still tests us on the things he missed out (this being one of them) So, I am a little stuck from this point on since I am not sure what the speed would be, since we have not been told what it is nor how to find it out.

I tryed to look up the speed online and what I found (hopfully corect) is 343 m/s,

## The Attempt at a Solution

My attempt.

λ1-λ2=v/f1 - v/f2

343/95.5 = 3.59(2dp) - 343/102.7 = 3.34 (2dp)

= 3.59-3.34

=0.25m

Now, I am not sure if this is corect, since its actually a multi choice on the answer and the nearest answer is actually 0.22m (interactive test so told me that the right answer when expermented)

my main problem is where did I go wrong to get 0.25 where he got 0.22.

Anyone able to give me some help/advice on this?

thanks

Ritchie.

p.s. really sorry on spelling, can't attach my disleaxer form on here (smiles)