Question Answers

Sahay Sir > Question Answers > Cengage JEE Mains Physics by B.M Sharma > Chapter 26 - Geometrical Optics > A convex lens of focal length 20cm and a concave lens of focal length f are mounted coaxially 5cm apart. Parallel beam of light incident on the convex lens emerges from the concave lens as a parallel beam. Then, f in cm is

A convex lens of focal length 20cm and a concave lens of focal length f are mounted coaxially 5cm apart. Parallel beam of light incident on the convex lens emerges from the concave lens as a parallel beam. Then, f in cm is

at which it will be totally internally reflected is the angle of incidence The velocity of light in a medium is half its velocity in air. If ray of light emerges from such a medium into air