Question

(2) At what distance from a concave mirror of
focal length 2.5 m should a boy stand so that his
image is half his height?
mirror​

Answer 1

Answer:

Magnification=height of the image/height of the object=-image distance/object distance

Let the actual height be x

=

x

(

2

x

)

=

2

1

2

1

=

u

−v

Usingsignconverstion,

2

1

=

u

v

u=2v

That is object distance is twice the image distance.

So, the object should be placed at the center of curved and the image will be formed at focus.

Object should be placed at center of curvature 2(2.5)=5cm

The image will be formed at focus =2.5 cm