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A bright spot is situated 60 CM in front of a convex mirror the mirror forms a virtual image 20 CM behind it. the focal length of the mirror​ is?

User Xdazz
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Final answer:

The focal length of the convex mirror is -30 cm.

Step-by-step explanation:

To find the focal length of a convex mirror, we can use the mirror equation, which is given by:

1/f = 1/do + 1/di

In this case, the object distance (do) is 60 cm and the image distance (di) is -20 cm (since the image is virtual and located on the same side as the object).

Plugging in the values, we get:

1/f = 1/60 + 1/-20

Simplifying the equation, we find that the focal length of the mirror is -30 cm.

The focal length of a convex mirror is considered negative.

This is because convex mirrors diverge light rays that are parallel to the mirror's principal axis.

In a convex mirror, the focal point is the point where the extended reflected rays appear to diverge from when projected backward.

User TCHdvlp
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