Calculating Frequency & Wavelength of Em Radiation
I. Calculating Frequency & Wavelength of EM radiation
Defining variables
Example:
What is the variable that we use to represent frequency (Hz)? = F (aka Ď…)
What is the variable that we use to represent wavelength (m) = w
What is the variable that we use to represent?
Speed of Light (m/s) = c
Note: all Electromagnetic Spectrum Waves travel at this same speed
Speed of light is a constant.
How many m/s does light travel?
3.00 x 10^8
Deriving equations
Given the formula ……C = F*W (aka c = υ*λ)
What is the formula for calculating F (aka Ď…)? F = c/w
What is the formula for calculating W (λ)? W = C/F
Calculating Frequency (F) and Wavelength (W)
Show your work! Use a calculator and do the actual math – dont just leave the answer as a fraction!
Violet light has a wavelength of 4.10 x 10-12 m. What is the frequency?
f=c/w
=3.00 x 10^8/4.10 x 10^12
=0.73 x 10^20
=7.3 x 10^19m
Green light has a frequency of 6.01 x 1014 Hz. What is the wavelength?
f=c/w
=3.00*108/6.01×1014
=0.499*10-6 m
= 4.99*10-7 m
What is the wavelength (in meters) of the electromagnetic carrier wave transmitted by The Sports Fan radio station at a frequency of 640 kHz? (Hint: convert kHz into Hz by multiplying by 103.)
f=6.4×10(3+2) = 6.4×105
w=3.00×108/6.4*105
0.47 x 10(8-5) Hz
=0.47 x103 Hz
= 4.7×102 Hz
Calculate the wavelength of radiation with a frequency of 8.0 x 1014 Hz.
w=C/F
w=c/f
=3.00×108/8.0*1014
=0.375×10(8-14)
=0.375×10-6 m
=3.75X10-7 m