Question

A 2cm high object is placed at a distance of 32cm from a concave mirror.the image is real,inverted and 3cm in size.find the focal length of the mirror and the position where the image is formed

Answer 1

$\textbf{Answer is in Attachment !}$

Answer 2

Answer:

13.2

Explanation:

ANSWER

Image is inverted  so magnification must be negative.  

m=  

objectheight

imageheight

​  

=  

2

−3

​  

=−1.5

Also  object distance is u=−32cm

We know m=−  

u

v

​  

 

−1.5=−  

−32

v

​  

 

Position of object from lens is v=−48cm

We know  

f

1

​  

=  

v

1

​  

+  

u

1

​  

 

f

1

​  

=  

−48

1

​  

+  

−32

1

​  

 

f=−19.2cm