Electromagnetic Radiation Light as Waves Worksheet
Use the following equation to solve the following problems:
c = λν
c = the speed of light (2.998 x 108 m/sec)
λ= wavelength measured in meters.
ν= frequency (unit is sec-1 or hertz (Hz))
Conversions
1nm = 10-9 m
109 = 1m
102 cm = 100cm = 1m
1. What is the frequency in hertz of red light having a wavelength of 710 nm?
2. Ozone protects the earth's inhabitants from the harmful effects of ultraviolet light arriving from the sun. This shielding is a
maximum for UV light having a wavelength of 295 nm. What is the frequency in hertz of this particular wavelength of UV
light?
3. Radar signals are also part of the electromagnetic spectrum in the microwave region. A typical radar signal has a wavelength
of 3.19 cm. What is the frequency in hertz?
4. AM radio dials are calibrated in frequency. A certain AM Brockville radio station broadcasts at a frequency of 830 kHz.
What is the wavelength of these radio waves expressed in meters?
Use the following equations to solve the following problems:
E = nhν c = λν
E = energy in Joules (J) c = the speed of light (2.998 x108 m/sec)
h = plank’s constant 6.626 x10-34 J s λ = wavelength measured in meters.
n = integer (number of photons) ν = frequency (unit is sec-1 or hertz (Hz))
5. Sodium vapor lamps are used to sometimes light streets. If the frequency of the light coming from them is 5.09 x 1014 Hz
what is the energy in each photon?
6. What is the energy of each photon of red light that has a frequency of 4.0 x 1014 Hz?
7. Calculate the energy in joules/photon for green light having a wavelength of 550 nm.
8. Microwaves are used to heat food in microwave ovens. The microwave radiation is absorbed by moisture in the food. This
heats the water, and as water becomes hot, so does the food. How many photons having a wavelength of 3.00 mm would have
to be absorbed by 1.00 g of water to raise its temperature by 1oC? It takes 4.184 J of energy to heat this much water.
9. What is the relationship between frequency and wavelength? (Direct or Inverse)
10. What is the relationship between frequency and energy? (Direct or Inverse)
