Question

The focal length ſ =(10cm). At what distance object should be placed to get an image twice size of object



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Answer 1

Answer:

Answer is given in the pic.

Hope this helps you

Answer 2

Convex lens gives the real and double-sized image when the object is placed exactly between the focus and radius of curvature.

We have,

f

1

=

v

1

−

u

1

m=

u

v

=2 or v=2u

∴

f

1

=

2u

1

−

−u

1

=

2u

1

+

u

1

=

2u

3

or

10

1

=

2u

3

or u=15cm