Question

the image........................ And fast get 10 points question 11​

Answer 1

Here image distance v = -40cm

Also, m = -1

Therefore, image formed is on the same size as the object

By magnification formula,

m = -v/u

-1 = 40/u

-40cm = u

Thus object is placed 40cm towards the left of the mirror

Now,

By mirror formula,

1/f = 1/v + 1/u

1/f = -1/40 - 1/40

1/f = -2/40

f = -20cm

If object is moved 20cm towards the mirror, object distance = -40 + 20 = -20cm

So, once again by mirror formula

1/f = 1/v + 1/u

-1/20 = 1/v - 1/20

1/v = -1/20 + 1/20

1/v = 0

v = 1/0 = Not defined or Infinity

Thus, image will be formed at infinity in this case