Question

diagram of concave refracting surface when light goes from denser to rarer medium

Answer 1

when light passes though denser to raeer mediam light bends away from normal.

Answer 2

A refracting surface, which forms a part of a sphere of transparent refracting material, is called spherical refracting surface

XY is the refracting surface.

P is the pole of spherical refracting surface. C is centre of curvature of spherical refracting surface.

m1, m2 are the absolute refractive indices of the two media.

Assumption: In dealing with refraction at spherical refracting surface, we assume.

The object to be a point lying on the principal axis of the spherical refracting surface.The aperture of the spherical refracting surface is small.The incident and refracted rays make small angles with the principal axis of the surface so that sini » i and sinr » i

The sign convention used in mirror is applicable for spherical refracting surfaces.

Refraction from Rarer to Denser Medium at a Convex Spherical Refracting SurfaceBack to Top
Real ImageBack to Top

Consider a spherical surface XY convex to the incident ray OA. The point O is a point object and I is the image of the point object where the refracted rays actually meet.

From A draw a perpendicular on the axis so as to meet M

In triangle OAC, i = a + g

According to Snell's law

As the aperture is close, M is close to P.

Using the sign convention, we put

PO = -u , PI = +v, PC = R

OR