Question

What is meant by focal length of a lens
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Answer 1

The focal length of a lens is the distance from the center of the lens to its focal point, where parallel rays of light converge or appear to diverge. It is typically measured in centimeters (cm).

Step-by-step explanation:

The focal length of a lens refers to the distance from the center of the lens to its focal point. The focal point is the location where parallel rays of light converge or appear to diverge after passing through the lens.

For a convex lens, the focal length is positive, and for a concave lens, the focal length is negative. The unit of measurement for focal length is typically centimeters (cm).

For example, if the focal length of a lens is given as 8.00 cm, it means that when parallel rays of light pass through the lens, they will converge at a point 8.00 cm away from the lens.

Answer 2

Focal length, usually represented in millimeters (mm), is the basic description of a photographic lens.

Step-by-step explanation:

The longer the focal length, the narrower the angle of view and the higher the magnification. The shorter the focal length, the wider the angle of view and the lower the magnification.