2. Remember that all types of EM waves move at the speed of light (3.0 x 10 8 m/s).

3. Since all EM waves travel at the same speed, this formula is used for all EM waves. c = λ ν VariableRepresent s Units cSpeed of light m/s λwavelengthm but sometimes nm is used νfrequencyHertz (Hz) or 1/s

4. What is the wavelength of light that has a frequency of 4.3 x 10 13 Hz in a vacuum? λ = c / ν λ = (3.0 x 10 8 m/s) / (4.3 x 10 13 Hz) λ = 7.0 x 10 -6 m What is the frequency of an EM wave that has a wavelength of 8.2 x 10 -9 m is a vacuum? ν = c / λ ν = (3.0 x 10 8 m/s) / (8.2 x 10 -9 m) ν = 3.7 x 10 16 Hz

5. All EM waves have different amounts of energy based upon their frequency E = h ν Planck’s constant will always be 6.626 x 10 -34 J*s VariableRepresent s Units EEnergyJoules (J) hPlanck’s Constant J * s νFrequencyHertz (Hz) or 1/s

6. How much energy does an EM wave have in a vacuum if its frequency is 5.83 x 10 12 Hz? E = h ν E = (6.626 x 10 -34 J*s) x (5.83 x 10 12 Hz) E = 3.86 x 10 -21 J What is the frequency of an EM wave if it has 7.49 x 10 - 12 J of energy? ν = E / h ν = (7.49 x 10 -12 J) / (6.626 x 10 -34 J*s) ν = 1.13 x 10 22 Hz