How is the grating spacing d found from the number of lines per metre N on a diffraction grating?

d = 1/N, so a grating with more lines per metre has a smaller grating spacing.

State the equation for the condition for diffraction maxima from a grating.

d sin θ = nλ, where d is grating spacing, θ is diffraction angle, n is order number, and λ is wavelength.

In the diffraction grating equation d sin θ = nλ, define each symbol.

d is the grating spacing (distance between adjacent slits), n is the order number (an integer), θ is the angle of diffraction, and λ is the wavelength of the light.

OCR A-Level Physics A H556

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Photon energy and the diffraction grating

4 things to know
Papers 1, 2 and 3

Overview

Recall questions on photon energy in terms of wavelength and frequency, and using a transmission diffraction grating: grating spacing, d sin θ = nλ and calculating wavelength.

What you need to know

Answer each one before you reveal it.

Your recallNot started

Numbers

State the equation that relates the energy of a photon to its wavelength, and describe the relationship between photon energy and wavelength.

Key term

How can a transmission diffraction grating be used to determine the wavelength of light?

Key term

Explain why blue light photons carry more energy than red light photons.

Numbers

What equation would you use to calculate photon energy if you know the frequency of the radiation?

Questions from this subtopic

Each one with the model answer underneath.

1
State the equation that relates the energy of a photon to its wavelength.
Model answer
E = hc/λ, where E is photon energy, h is Planck's constant, c is the speed of light, and λ is wavelength.
2
Explain why blue light photons carry more energy than red light photons.
Model answer
Blue light has a shorter wavelength than red light. Since E = hc/λ, a smaller wavelength results in a larger photon energy.
3
How is the grating spacing d found from the number of lines per metre N on a diffraction grating?
Model answer
d = 1/N, so a grating with more lines per metre has a smaller grating spacing.
4
How can a transmission diffraction grating be used to determine the wavelength of light?
Model answer
By measuring the angles at which maxima occur, the wavelength can be calculated using the diffraction grating equation.
5
State the equation for the condition for diffraction maxima from a grating.
Model answer
d sin θ = nλ, where d is grating spacing, θ is diffraction angle, n is order number, and λ is wavelength.
6
In the diffraction grating equation d sin θ = nλ, define each symbol.
Model answer
d is the grating spacing (distance between adjacent slits), n is the order number (an integer), θ is the angle of diffraction, and λ is the wavelength of the light.

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Photon energy and the diffraction grating

Overview

What you need to know

State the equation that relates the energy of a photon to its wavelength, and describe the relationship between photon energy and wavelength.

How can a transmission diffraction grating be used to determine the wavelength of light?

Explain why blue light photons carry more energy than red light photons.

What equation would you use to calculate photon energy if you know the frequency of the radiation?

Questions from this subtopic

State the equation that relates the energy of a photon to its wavelength.

Explain why blue light photons carry more energy than red light photons.

How is the grating spacing d found from the number of lines per metre N on a diffraction grating?

How can a transmission diffraction grating be used to determine the wavelength of light?

State the equation for the condition for diffraction maxima from a grating.

In the diffraction grating equation d sin θ = nλ, define each symbol.

Other ways to work this

What is inside Levo

See a huge jump in your memorisation

Cram a whole paper in one sitting

Blank Blitz consolidates the facts

Build It trains answer structure

Test It catches misconceptions

Brain Breaks between sessions

Every question in Astrophysics and Cosmology, on a schedule.