Eduqas A-Level Physics A420QS
Basic Physics
Kinematics
Dynamics
Energy Concepts
Circular Motion
Vibrations
Kinetic Theory
Thermal Physics
Conduction of Electricity
Resistance
D.C. Circuits
Capacitance
Solids Under Stress
Electrostatic and Gravitational Fields of Force
Using Radiation to Investigate Stars
Orbits and the Wider Universe
The Nature of Waves
Wave Properties
Refraction of Light
Photons
Lasers
Nuclear Decay
Particles and Nuclear Structure
Nuclear Energy
Magnetic Fields
Electromagnetic Induction
Option A: Alternating CurrentsOption A
Option B: Medical PhysicsOption B
Option C: The Physics of SportsOption C
Option D: Energy and the EnvironmentOption D
Mathematical Requirements (Appendix C)
Wave Properties
Young's double slit experiment
- 3 things to know
- Component 3
Overview
Arrangement of Young's double slit experiment and seen on the screen in Young's experiment with monochromatic light.
What you need to know
Answer each one before you reveal it.
Describe the arrangement of Young's double slit experiment.
What is seen on the screen in Young's experiment with monochromatic light?
Questions from this subtopic
Each one with the model answer underneath.
- 1
Describe the arrangement of Young's double slit experiment.
Model answer
Monochromatic light illuminates two narrow parallel slits close together, and the light from them falls on a screen a large distance away.
- 2
What is seen on the screen in Young's experiment with monochromatic light?
Model answer
A series of equally spaced bright and dark fringes, brightest at the centre and fading further out.
- 3
Give the equation used to find the wavelength in Young's experiment and define every symbol.
Model answer
λ = ay/D, where λ is the wavelength in metres, a the separation of the slits in metres, y the fringe spacing in metres and D the distance from the slits to the screen in metres.
- 4
Why must the two slits be very close together?
Model answer
A small slit separation gives a large fringe spacing, since the spacing is inversely proportional to it, so the fringes can be measured.
- 5
Why is the screen placed a long way from the slits?
Model answer
The fringe spacing is proportional to that distance, so a large distance makes the fringes wide enough to measure accurately.
- 6
Two slits 0.40 mm apart give fringes 2.6 mm apart on a screen 1.80 m away. Calculate the wavelength.
Model answer
λ = ay/D = 4.0 × 10⁻⁴ × 2.6 × 10⁻³ ÷ 1.80 = 1.04 × 10⁻⁶ ÷ 1.80, which is 5.8 × 10⁻⁷ m, or 580 nm.
Other ways to work this
The same content, four other ways.
What is inside Levo
Six ways to work the same material.
Every question in Wave Properties, on a schedule.
Attempt a question from memory, write the correct version, then attempt it again. Levo records the jump between your first attempt and your last, and brings each question back on the day you are due to forget it.
Or £46 a year, about £3.83 a month. Cancel anytime.