Question

a concave mirror of focal length 8 cm forms an inverted image of an object placed at a certain distance .if the image is twice as large as the object ,where is the image formed ?
please tell with full solution please please ​

Answer 1

Answer:

Image is inverted so magnification ratio should be negative.

Since the object size is double so magnification ratio m=−2

now the object distance from mirror  u=−12

So m=−  

u

v

​  

 

−2=−  

−12

v

​  

 

v=−24cm

image is formed at 24 cm from mirror in same direction of object.

Now be know  

f

1

​  

=  

v

1

​  

+  

u

1

​  

 

f

1

​  

=  

−24

1

​  

+  

−12

1

​  

 

f=−8cm