Question

an object of size 7 cm is placed at 25 in front of concave mirror of focal length 15 CM at which distance from the mirror should a screen be placed so that we can get sharp and clear image find the nature and size of the image​

Answer 1

Heya mate ur answer is

Given

 Size of the object [o] = +7cm

  F = -18cm

  U= -27cm

 V = ?

 1/f = 1/v+1/u

 1/-18cm = 1/v-1/27

  1/v= -1/54 v = -54cm

Since Vis – ve screen should be placed at 54cm in front of the mirror.

Size of the image : m= I/O= -v/u I/7=-[54/27] I= -14cm

Nature of the image : image is real , inverted .

Hope it helps