Optics Answers

A person can see clearly objects lying between 15cm and 100cm from the eye.what will be the range of his vision if he wears close fitting spectacles having a power of 0.8 D?

If your eye glasses have focal length 60cm what is your near point?

In a double slit experiment, the two slits are 1 mm apart and the screen is placed 1 m away A monochromatic light of wavelength 500 nm is used. What will be the width of each slit for obtaining ten maxima of double slit within the central maxima of single slit pattern? (a) 0.5 mm (b) 0.02 mm (c) 0.2 mm (d) 0.1 mm

In an astronomical telescope in normal adjustment a straight black line of length L is drawn on inside part of objective lens. The eye-piece forms a real image of this line. The length of this image is I. The magnification of the telescope is
(a) L+I/L-I
(b) L/I
(c) L/I+1
(d) L/I-1

In fibreoptics the type of cable is chosen by
a) matching the diameter of the cable to the wavelength
b) distance required to travel
c) the strength of signal needed

A mirror.
Option A. refracts all light.
Option B. reflects all light.
Option C. absorbs a percentage of light.

Which one is true

A small aperture is illuminated with a parallel beam of λ = 628nm . The emergent beam has an angular divergence of 2∘ . The size of the aperture is.

A student uses a converging lens to produce an enlarged virtual image of a scale he whishes to read accurately. The focal length is 10cm. What is the appropriate distance between the scale and the lens?

There is a convex spherical mirror with a focal length of 16.00 cm. When a figurine is placed in front of it, an upright image 3.00 cm tall is formed 6.80 cm behind the mirror.
Find the position of the figurine
Find the magnification of the image

Calculate the critical angle of a material having a refractive index of 1.52 when light passes from the material to air