Question

an insect is sitting in front of a plane mirror starts moving from the mirror at a speed of 5 m/s. At what distance will its image be formed from the mirror after 1.5s? if the size of the insect is 10cm what will be the size of image after 1.5 s?

Answer 1

Equivalent focal length in air,

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1

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2

When glycerin is filled inside, glycerin lens behaves like a diverging lens of focal length (-f)

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1

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F

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2

1

solution

Answer 2

Answer:

7.5m, erect and virtual, 10 cm

Explanation:

Distance: u can find yourself

Nature of image: the image formed by plane mirrors are always virtual and erect as they cannot taken on screen

Size after 1.5s: size does not changes with time