Question

At what distance an object must be placed in front of a convex mirror of focal length 15 cm So that an image is form 10 cm behind the mirror​

Answer 1

From lens formula,  

v

1

​  

−  

u

1

​  

=  

f

1

​  

⇒  

v

1

​  

=  

10

1

​  

−  

15

1

​  

 

or v=30cm.