Question

An object is placed 20 cm from pole of a concave mirror. Find out the position of image from pole
if the focal length of concave mirror is 10 cm.

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Answer 1

U=-20cm(sign convention)

F=-10cm(since concave mirror)

V=?...

By mirror formula we have

1/f=1/v+1/u

1/v=1/f-1/u

1/v=u-f/uf(Reciprocal)

v=uf/u-f

v=(-20)(-10)/-20-(-10)

v=(-20)(-10)/-10

v=-20cm

Thus, from this we can conclude that the image distance is equal to object distance

Nature of image is real, inverted and same size so magnification is '1'

Hope you understood the problem clearly

Answer 2

answer is mentioned above.u, v &f should be negative for concave mirror