a concave mirror and a converging lens have the same focal length in the air which one of the - Physics -

Question

a concave mirror and a converging lens have the same focal length
in the air which one of the two will have greater focal length when
immersed in water? explain why?

Sandeep K. Gupta · Accepted Answer

Dear Student,

focal lenth of lens in water is given by1f=μgw-11R1-1R2Because RI of water is less than RI of glass hence focal length of lens increases in water as compare to its focal lenth in air
Because focal length of mirror does not depends on the RI of the medium hence focal lenght of mirror remains same in the water
Hence lens has more focal length in  water

Regards

a concave mirror and a converging lens have the same focal length in the air. which one of the two will have greater focal length when immersed in water? explain why?