Question

a concave mirror has a radius of curvature of 0.4 m find the position and the size of the image of an object 0.2 m high placed 0.8 m infront of the mirror

Answer 1

isn't there a formula for this? What difficulty are you having with it?

Answer 2

f=R/2
f =-0.2m
Ho(height of object)=+0.2 m
U(distance b/w Pole and object)=-0.8m
V(distance between pole and image)=?
Height of image (hi)=?
Formula- 1/f=1/v+1/u
1/f=1/v- 1/u
1/-0.2-(1/-0.8)=1/v
-1/2+1/8=1/v
-4+1÷8=1/v
-3v=8
v=-2.6m (distance b/w pole and image)
m=-v/u
m=-(-2.6)/-0.8
m=3.25
m=hi/ho
3.25=hi/0.2
hi=0.65 m