Question

the
3. It is required to throw an image,
magnified two times, on a screen placed at
a distance of 6cm from the object. Find the
focal length and the lens required.​

Answer 1

Answer:

Please mark as brainliest answer

Explanation:

m=2

m=v/u=2

v=2u

also

v=u+6

2u=u+6

u=6

v=2u

v=12

the object distance is always negative

so

u=-6

also the image is on the same side of the object .

so

v=-12

using lens formula

1/f=1/v-1/u

1/f=1/-12-1/-6

1/f=1/12

f=12

Focal length is positive.

So,it is a convex lens.