A lens is held directly above a pencil lying on a floor and forms and image of it. After the lens has been moved vertically a distance equal to its focal length it forms image of equal size to the previous image. If the length of the pencil is 8 centimetre the length of the image is?

An oscillator consists of a block of mass 512 g connected to a spring. When set into oscillation with amplitude 34.7 cm, it is observed to repeat its motion every 0.484 s. Find (a) the period, (b) the frequency, (c) the angular frequency, (d) the force constant, (e) the maximum speed, and ( f ) the maximum force exerted on the block.

A PLANE TRANSMISSION GRATING HAS 45000 LINES. DETERMINE ITS RESOLVING POWER IN THE SECOND ORDER FOR WAVELENGTH OF 5000A.

A PLANE TRANSMISSION GRATING HAS 45000 LINES. DETERMINE ITS RESOLVING POWER IN THE SECOND ORDER FOR WAVELENGTH OF 5000A.

If V-numer of a multi mode fiber is 3. Calculate the no.of modes if it is step index and graded index fiber multimode fiber (rounded off)?

What is the difference between angular position and angular fringe width... I always get confused .