Question

list the cartesian sign convention for reflection of light by spherical mirrors. Draw a diagram and apply these conventions for calculating focal length and nature of a spherical mirror which forms a 1/3 times magnified virtual image of an object placed 18 cm in front of it.

Answer 1

The focal length of the mirror is 9 cm.

Explanation:

Since the image formed is magnified and virtual, the mirror is convex.

According to the convention

u = - 18 cm

m = 1/3 = −   v/u

v = 6 cm

By using lens mirror formula:

1/v + 1/u = 1/f

f = uv /  u + v

f = -18 x 6 / - 18 + 6

f = - 108 / - 12

f = 9 cm

Thus the focal length of the mirror is 9 cm.

Also learn more

An object is placed at 20 cm from a concave mirror of focal length 10 cm. find the position and the nature of the image formed. draw ray diagram to explain the formation of image (not to scale) ?

https://brainly.in/question/1123369

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Answer 2

Answer:this is the correct answer as per ulike

Explanation: