Question

An object is placed at a distance of 10 cm in front of a concave lens of focal length 10 cm.
Find : (a) position of image
(b) The size of image in relation to the object.

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Answer 1

Answer:

1) 5cm on the left side of the lens

2) Diminished

3) Dioptre (D)

Explanation:

Assuming the object to be placed on the left side of the lens,

f= -10cm for a concave lens.

u= -10cm ( distance from the pole to the object is opposite to the direction of light.)

v=?

1/f=1/v - 1/u (Lens formula)

Substitute with proper signs and solve for v.

We get v= -5cm which means it is on the left side of the lens.