variation: what is length of wave with frequency of 800 kHz?

[patti72458]

Wavelength and Frequency

THe wavelenght W of a radio wave varies inversely as its frequency F. A wave with a frequency of 1200 kilohertz has a lenght of 300 meters. What is the lenght of a wave with a frequency of 800 kilohertz?

please help set up

 

[tkhunny]

Just write these down and remember them.

Direct Variation

A = k*B

Inverse Variation

A = k/B

Joint Variation

A = k*B*C

"Wavelength varies inversely with frequency"

W = k/F

Given Information (There MUST be something to solve for 'k'.)

300 m = k/(1200 kHz)

k = 360,000 m*kHz

So, ...

W = (360,000 m*kHz)/F

Problem Statement

F = 800 kHz

Plug and Chug.