Rays of light always travel in a straight line.This phenomenon is called:
Total internal reflection
Rectilinear propagation
Scattering of light
None of these
Radius of curvature, r =
f/2
2f
2/3 f
f
A solar eclipse occur only on a:
New moon day
Full moon day
Gibbous moon
What occurs when the tip of the umbra falls on the earth?
Partial solar eclipse
Partial lunar eclipse
Annular solar eclipse
