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

### Chapter: 18. Geometrical Optics

#### Subject: Physics - Class 11th

##### Q. No. 5 of Exercises

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5
##### A candle flame 1.6 cm high is imaged in a ball bearing of diameter 0.4 cm. If the ball bearing is 20 cm away from the flame, find the location and the height of the image.

1.0 mm inside the ball bearing, 0.08 mm

diameter of ball bearing, d= 0.4cm

Height of the object, h= 1.6 cm

The distance of object from the ball, u = 20cm

Using the mirror formula,

According to the figure shown,

The distance of the object from the ball is taken as u=-20cm

And the focal length of the ball is taken as positive

Putting the value or R and u

The image formed will be inside the ball bearing

Magnification m= -

Height of the image = 16/200 = 0.8 m

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