Write an Explanation. Principal focus - Science and Technology 1

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Definition
Explain

Write an Explanation.

Principal focus

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Solution

Rays travelling parallel to the principal axis of a lens, after refraction, converge to a point on the principal axis or diverge in such a way that they appear to be coming out of a point on the principal axis. This point is called the principal focus of the lens.

Concept: Lens
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Chapter 7: Lenses - Write an Explanation

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