Question

At what distance from a convex lens of focal
length 2.5 m should a boy stand so that his image
is half his height ?
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Answer 1

Explanation: hope it's helpful to you mark me brainliest and thank my answer please please please please

Magnification=height of the image/height of

the object = -image distance/object distance

Let the actual height be x

=(x/2)/x

=1/2

1/2= -v/u

Using sign convention,

1/2 v/u

U=2v

That is object distance is twice the image

distancee

So, the object should be placed at the centre

of curvature and the image will be formed at

focus.

Object should be placed at centre of

curvature =2(2.5)=5cm

The image will be formed at focus =2.5cm