Question

An object is placed in front of spherical
mirror of focal length 20 cm
which form its image twice as size of object.
Find all possible values of object distance
image distance , nature of mirror and
image​

Answer 1

Answer:Now let the object distance which is u=-x such that v= -2x...(1)

, now m=v/-u

, m=-2x/-x=2/1

, such that m=v/u=2/1

Now apply mirror formulae

Which is, 1/v+1/u=1/f

Now put all the values given in que.

1/2x+1/x=1/-20(from1)

, now take L. C. M of the following:

1+1/-x=1/20

2/-x=1/20

Now x=-40cm

Now if x=-40 then v=?

By using 1

V=-2×-40=+80cm

Now as we can see that u is -, v is + and fish also + such that we can say that nature of image is erect and diminished.

Explanation: