Question

an object is placed before a concave lens of focal length 12 centimetre the size of the image formed by a lens is half the size of the object calculate the distance of the object from the lens.
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Answer 1

Answer:

We are given that

An object is placed before a concave lens of focal length 12 CM the size of the image formed by the lens is half the size of the object calculate the distance of the object from the lens

We know that

1/f = 1/v – 1/u

1/v = 1/f + 1/u

1/v = f + u / fu

So,cross multiplying

v = fu / f + u

Image formed is half the size of the object.

1/2 = fu / u + f / u

For

f = - 12

1/2 = - 12 u / (u – 12) / u

So

u – 12 = - 24

So,

u = - 12

Explanation:

Answer 2

hello mate

her your answer

the answer is u= -12

Mark it as brainlist....