Wave Optics

Front

Ray model Noun

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[ray mod-l]

Back

Ray model

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A model of waves that uses an arrow, called a ray, to represent the direction the wave is traveling.

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Example: The ray model shows light traveling in straight lines called rays. This diagram shows a light ray from a source hitting a mirror and reflecting off it.

Front

Ray Noun

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[ray]

Back

Ray

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An arrow used in a wave model to represent the direction of wave travel, drawn perpendicular to the wave fronts.

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Example: This diagram shows a ray as a straight line representing the path of light, which bends (refracts) when it passes from air into water.

Front

Huygens' wave model Noun

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[hoy-genz wayv mod-l]

Back

Huygens' wave model

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A model representing every point on a wave front as a source of semicircular wavelets that spread out forward.

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Example: Each point on an incoming wave front acts as a source for tiny new wavelets, which together form the new reflected wave front.

Front

Wavelet Noun

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[wayv-let]

Back

Wavelet

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A small, semicircular wave that spreads out from a point on a wave front, as described by Huygens' principle.

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Example: Each point on a wave's edge (old wavefront) creates a tiny new circular wave (a wavelet). All these wavelets combine to form the next wave's edge.

Front

Diffraction Noun

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[dih-frak-shun]

Back

Diffraction

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The bending and spreading of a wave as it passes around the edges of an opening or an obstacle.

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Example: Sound waves bend as they pass through a doorway, allowing someone to hear around a corner. This bending of waves is called diffraction.

Front

Reflection Noun

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[ri-flek-shun]

Back

Reflection

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A phenomenon that occurs when a wave or object bounces off an interface or another object.

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Example: This diagram shows parallel light rays hitting a smooth surface and bouncing off in a single, predictable direction, which demonstrates specular reflection.

Front

Normal line Noun

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[nor-muhl line]

Back

Normal line

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An imaginary line drawn perpendicular to a surface at the point where a ray of light strikes it.

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Example: This diagram shows that the normal line is an imaginary line drawn perpendicular (at 90°) to a surface, like a mirror, at the exact point where a light ray hits.

Front

Virtual image Noun

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[vur-choo-uhl im-ij]

Back

Virtual image

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An image formed by light rays that appear to originate from a point but do not actually pass through it.

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Example: This diagram shows how a convex mirror reflects light rays from an object, making them appear to come from a point behind the mirror, creating a virtual image.

Front

Real image Noun

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[reel im-ij]

Back

Real image

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An image formed by light rays that actually converge and originate from a point; it can be projected onto a screen.

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Example: This image shows how light interacts with different materials, illustrating the concept of light behavior but does not specifically define 'real image'.

Front

Refraction Noun

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[ri-frak-shun]

Back

Refraction

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The change in direction of a wave as it passes from one medium to another, caused by a change in wave speed.

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Example: This diagram shows a ray of light bending as it passes from one substance (Medium 1) to another (Medium 2), illustrating the concept of refraction.