There are alternate light and dark fringes on the screen.The dark fringes become narrower than the bright fringes if the slit is too wide, and contrast is lost.There is reinforcement at bright fringes (light waves arrive in phase) and cancellation at dark fringes (light waves arrive 180° out of phase).Fringe SeparationThe distance from the centreof a bright light fringeto the centre of the next bright light fringeis called the fringe separation.
Wavelength and Interference
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Specification: AQA Physics (7407), AS-level, 3.3.2.1 Interference. Topic: Optics.
Key terms in this lesson
- Equilibrium
- An object is in equilibrium when the resultant force and the resultant moment acting on it are both zero.
- Centre of mass
- The single point at which the entire weight of an object may be considered to act.
- Resistance
- The ratio of the potential difference across a component to the current flowing through it, measured in ohms.