Doubt in Physics -Ray Optics

[RoopikaG]

Hi All.

This is my first time in this forum.

i have a doubt in Physics -Ray Optics.

"focal length of concave lens changes with medium" .how...

Please help me.

Thanx.

[Noopur pandey]

Hi All.

This is my first time in this forum.

i have a doubt in Physics -Ray Optics.

"focal length of concave lens changes with medium" .how...

Please help me.

Thanx.

hye Roop..you can answer yuorself with the help of lens maker formula,where:
1/f=(refractive index of lens-1)[1/r-1/r`].

the focal lengh of any lens varies directly with refractive index of its medium.