Ray Optics

A: Ray optics assumes that light travels in a straight line which is disapproved by diffraction effects, yet the ray optics assumption is so commonly used in understanding location and several other properties of images in optical instruments. R: Typical sizes of apertures involved in ordinary optical instruments are much larger than the wavelength of light.

In geometrical optics a ray of light is defined as

When a ray of light travles from an optically more denser medium to an optically less denser medium, the angle of incidence is always _____ than the angle of refraction.

When a ray of light travels from an optically less denser medium to an optically more denser medium, the angle of incidence is always less than angle of refraction.

Assertion: Standard optical diffraction cannot be used for discrimination between different X-ray wavelengths. Reason: The grating spacing is not of the order of X-ray wavelengths.

A ray of light travels from an optically denser to rarer medium. The critical angle of the two media is C. The maximum possible deviation of the ray will be

An object of height 2.5 cm is placed at a distance of 15 cm from the optical centre 'O' of a convex lens of focal length 10 cm. Draw a ray diagram to find the position and size of the image formed. Mark optical centre 'O', principal focus F and height of the image on the diagram.

How is the optical rotation of an optically active compound measured and how is it expressed ?

A light ray is travelling through a ring of an optical fibre which is made of four different glasses (shown below) but each part has the same geometrical thickness. Their respective refractive indices are shown. The light ray will take the maximum time in crossing the part

(a) State Snell's law of refraction of light. (b) A transparent medium A floats on another transparent medium B. When a ray of light travels obliquely from A into B, the refracted ray bends away from from the normal. Which of these two media A or B are optically denser and why ?