## Book: HC Verma - Concepts of Physics Part 1

### Chapter: 18. Geometrical Optics

#### Subject: Physics - Class 11th

##### Q. No. 10 of Exercises

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10
##### A particle goes in a circle of radius 2.0 cm. A concave mirror of focal length 20 cm is place with its principal axis passing through the center of the circle and perpendicular to its plane. The distance between the pole of the mirror and the center of the circle is 30 cm. Calculate the radius of the circle formed by the image.

4.0 cm

radius of the object = 2cm

Focal length of the concave mirror, f = -20cm

The distance of the object from mirror, u = 30cm

Using mirror formula,

The image of the circle is formed at the distance 60cm in front of the mirror

Magnification m=

Radius of image= 2 x 2 cm = 4cm

Hence, radius of the image formed = 4cm

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