Question

an object of height 2 cm is placed 20cm distance in front of a concave mirror whose focal length is 15 CM calculate the height of the image​

Answer 1

$\huge\tt\purple{♬•Answer:}$

Given that:

hₒ=2cm

u(object-distance) =20cm

f=15cm

Now, applying mirror equation:

$\huge \frac{1}{f}=\frac{1}{u}+\frac{1}{v}$

$\huge\frac{1}{15}=\frac{1}{20}+\frac{1}{v}$

$\huge\frac{1}{v}=\frac{1}{15}-\frac{1}{20}$

$\huge \frac{1}{v}=\frac{4-3}{60}$

$\huge \frac{1}{v}=\frac{1}{60}$

$\huge v=60cm$

Now, we know that..

$\huge\frac{h_e}{h_o}=\frac{-v}{u}$

$\huge\frac{h_e}{2}=\frac{-60}{20}$

$\huge{ h_e= -6 cm}$

That means height of the image is 6cm and is below principal axis..