A convex lens has power P . It is cut into two halves along its principal axis. Further one piece (out of the two halves) is cut into two halves perpendicular to the principal axis (as shown in figure

Question

A convex lens has power P . It is cut into two halves along its principal axis. Further one piece (out of the two halves) is cut into two halves perpendicular to the principal axis (as shown in figures). Choose the incorrect option for the reported pieces.

TestHub · Accepted Answer

Using Lens maker's formula, power is given by

$P = \frac{1}{f} = (μ - 1) (\frac{1}{R_{1}} - \frac{1}{R_{2}})$

When convex lens is cut into two parts, $P_{1} = \frac{1}{f} = (μ - 1) (\frac{2}{R}) = P$

When half convex lens is cut into two parts, $P_{2} = \frac{1}{f} = (μ - 1) (\frac{1}{R}) = \frac{P}{2}$

Power of lens, $P_{3} = \frac{1}{f} = (μ - 1) (\frac{1}{R}) = \frac{P}{2}$

Physics - Geometrical Optics Question with Solution | TestHub

Options:

Doubts & Discussion