Question

An object is 20cm in front of convex mirror if the image height is 1/5 times the object height determine 1. The image distance 2. The focal length 3. The properties of image

Answer 1

Step-by-step explanation:

It is given that,

Focal length

f=−20cm

hi=3ho

The image is three times the size of the object. So there are two cases.

Case 1. For real image

m=−uv=−3

v=3u

Using mirror’s formula

f1=v1+u1

−201=3u1+u1

u=3−80cm

Case 2. For virtual image

m=u−v=+3

v=−3u

Again using mirror’s formula

−201=−3u1+u1

u=3−40cm

The possible values of u are 3−80cmand3−40cm.