Question

An object of height 7 cm is kept at a distance of 30 in front of the concave mirror the focal length of the mirror is 15 cm at what distance from the mirror should a screen be kept so as to get a clear image? What will be the size and nature of the image

Answer 1

Answer:size of image is2.3cm and the nature of image is real and inverted.

Explanation:let, u be the object distance =-30 cm

v=image distance

f = focal length of mirror = -15cm

hi=height of image

ho=height of object

According to mirror formula,

1/f=1/v+1/u

1/v=1/15+1/30=1/10

v=10cm

Now, magnification of concave mirror;m =-v/u=hi/ho

-10/-30=hi/7

hi =7/3=2.3cm

Thus size of image is 2.3cm and nature of image is real and inverted.