A concave lens has focal length 15 cm . At what distance should the object from the lens be placed so that it forms an image at 10 cm from the lens? Also find the magnification produced by the lens.

Given: The image distance, v = - 10 cm The focal length, f = - 15 cm From the lens formula, 1 f = 1 v - 1 u ⇒ 1 - 15 = 1 - 10 - 1 u ⇒ 1 u = - 1 30 ⇒ u = - 30 cm The object should be placed at 30 cm from the concave lens. The magnification, m = v u = - 10 - 30 = + 0 . 33 The magnification produced by the lens is + 0 . 33 .

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Science for Tenth Class Part - 1 Physics>Chapter 5 - Refraction of Light>Very Short Answer Type Questions>Q 4

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10th CBSE

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A beam of light travelling in air is incident on water. Draw a ray diagram indicating the change in its path in water.

Important Questions on Refraction of Light

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10th CBSE

IMPORTANT

Science for Tenth Class Part - 1 Physics>Chapter 5 - Refraction of Light>Very Short Answer Type Questions>Q 5

A ray of light travelling in water emerges into air. Draw a ray diagram indicating the change in its path.

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Science for Tenth Class Part - 1 Physics>Chapter 5 - Refraction of Light>Very Short Answer Type Questions>Q 6

A ray of light travelling in air is incident on a parallel-sided glass slab (or rectangular glass slab). Draw a ray-diagram indicating the change in its path in glass.

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Science for Tenth Class Part - 1 Physics>Chapter 5 - Refraction of Light>Very Short Answer Type Questions>Q 7

A ray of light travelling in glass emerges into air. State whether it will bend towards the normal or away from the normal.

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Science for Tenth Class Part - 1 Physics>Chapter 5 - Refraction of Light>Very Short Answer Type Questions>Q 8

A ray of light travelling in air enters obliquely into water. Does the ray of light bend towards the normal or away from the normal? Why?

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10th CBSE