Class 12 NEET Physics Optics Questions Part 1

According to lens maker’s formula

1

f

=(

µg

µL

−1)(

1

R1

−

1

R2

)
where µg is the refractive index of the material of the lens and µL is the refractive index of the liquid in which lens is dipped. As the biconvex lens dipped in a liquid acts as a plane sheet ofglass, therefore
f=∞⇒

1

f

=0,∴

µg

µL

−1=0 or µg=µL