# Worksheet: The Quantization of Electromagnetic Radiation

In this worksheet, we will practice calculating the energy of a photon given its frequency or wavelength.

**Q1: **

A laser emits photons, each with a frequency of Hz. What is the total energy radiated by the laser? Use a value of J⋅s for the Planck constant. Give your answer in joules to 3 significant figures.

**Q2: **

Which of the following is the correct formula for the energy of a photon given its frequency, where represents the Planck constant and represents the speed of light?

- A
- B
- C
- D
- E

**Q3: **

What is the difference in the energy of a Hz photon and a Hz photon? Use a value of J⋅s for the value of the Planck constant. Give your answer in joules to 3 significant figures.

- A J
- B J
- C J
- D J
- E J

**Q4: **

What is the wavelength of a photon that has an energy of J? Use J⋅s for the value of the Planck constant and m/s for the value of the speed of light in free space. Give your answer in meters to 3 significant figures.

- A m
- B m
- C m
- D m
- E m

**Q5: **

What is the energy of a photon that has a wavelength of 400 nm? Use a value of J⋅s for the value of the Planck constant and m/s for the value of the speed of light in free space. Give your answer in joules to 3 significant figures.

- A J
- B J
- C J
- D J
- E J

**Q6: **

Photon has twice the frequency of photon . What is the ratio of the energy of photon to the energy of photon ?

**Q7: **

Photon A has a wavelength that is four times that of photon B. What is the ratio of the energy of photon A to the energy of photon B?

- A2
- B
- C
- D4
- E1

**Q8: **

What is the frequency of a photon that has an energy of J? Use a value of J⋅s for the value of the Planck constant. Give your answer in hertz to 3 significant figures.

- A Hz
- B Hz
- C Hz
- D Hz
- E Hz

**Q9: **

What is the difference in the energy of a blue photon, with a wavelength of 400 nm, and a red photon, with a wavelength of 700 nm? Use a value of J⋅s for the value of the Planck constant and m/s for the value of the speed of light in free space. Give your answer in joules to 3 significant figures.

- A J
- B J
- C J
- D J
- E J

**Q10: **

What is the frequency of a photon that has an energy of 3.00 eV? Use eV⋅s for the value of the Planck constant. Give your answer in hertz to 3 significant figures.

- A Hz
- B Hz
- C Hz
- D Hz
- E Hz

**Q11: **

What is the energy of a photon that has a frequency of Hz? Use eV⋅s for the value of the Planck constant. Give your answer in electron volts to 3 significant figures.

**Q12: **

What is the energy of a photon that has a frequency of Hz? Use a value of J⋅s for the value of the Planck constant. Give your answer in joules to 3 significant figures.

- A J
- B J
- C J
- D J
- E J

**Q13: **

A laser emits light with a wavelength of 200 nm. How many photons must be emitted by the laser for the amount of energy emitted to be 1 J? Use a value of J⋅s for the value of the Planck constant and m/s for the value of the speed of light in free space. Give your answer to 3 significant figures.

- A
- B
- C
- D
- E

**Q14: **

In this question, use a value of J⋅s for the Planck constant.

A gamma ray typically has a frequency of around Hz. Using this value, find the energy of a gamma-ray photon. Give your answer, in joules, to 3 significant figures.

- A J
- B J
- C J
- D J
- E J

A radio wave typically has a frequency of around Hz. Using this value, find the energy of a radio-wave photon. Give your answer in joules to 3 significant figures.

- A J
- B J
- C J
- D J
- E J

How many times more energetic is a gamma-ray photon of the given frequency than a radio-wave photon of the given frequency?

- A
- B
- C
- D
- E