Question

A 4.5cm needle is placed at 12cm away from a convex mirror of focal length 15cm give the location of image and magnification

Answer 1

i think u gonna understand this

Answer 2

height of the object needle h=4.5cm
object distance u =-12cm[-ve for convex mirror ]
focal length f =-15cm
using mirror formula,
1/V+1/u=1/f
1/V=1/f-1/u
1/V=1/-15-(1/-12)
1/V=1/-15+1/12
1/v=5-4/60
v=+60cm
magnification M =-V/u
M=-60/-12
M=+5