Question

An object 2 cm high is placed at a distance of 16 cm in front of a concave mirror which form a real image of 3 cm high find the focal length and position of image​

Answer 1

h1= 2cm

h2=-3cm

u=-16cm

m=-v/u=h2/h1

m=-v/-16=-3/2

v=-3×16/2

v=-24cm

1/v+1/u=1/f

1/-24+ 1/-16=1/f

1/f=(-2-3)/48

1/f=-5/48

1/f=-48/5

=9.6cm