Question

an object is placed at a distance of 20 cm from a convex mirror of focal length 3o cm..find position , nature & size of the image??

Answer 1

givendata
(u)object distance =-20cm
(f) focal length= 30cm
image size=?
position of image=?
nature of image=?
•.• 1/f=1/v+1/u
1/30=1/v+1/-20
1/30+1/20=1/v
2+3/60=1/v
5/60=1/v
1/12=1/v
v=12
•.• magnification=hi/ho= -v/u
= -12/-20
= 3/5
= 0.6cm
hence magnification is 0.6 then image is erect and diminished.
position of the image is 12cm