Basic Terms in Ray Optics

A man of height $h$ is walking away from a street lamp with a constant speed $v$. The height of the street lamp is $3h$. The rate at which of the length of the man's shadow is increasing when he is at a distance $10h$ from the base of the street lamp is:

A beam of light is generated by a laser is called-

The scattering of a beam of light by a medium containing small suspended particles is called _____.

The ray from the sun is an example of a parallel beam of light.

A ray model is very useful while studying the 

A ray of light is a straight line that has the same sense of propagation.

Define a ray of light.

Which of the following is the correct formula of speed of light in a medium(refractive index $\mu$)?

Which of the following phenomenon is studied under ray optics?

Differentiate between ray optics and wave optics.

What do you understand by the term "optics"?

The following graph depicts the inverse of magnification versus the distance between the object and lens data for a setup. The focal length of the lens used in the setup is

Distance between the object and the lens $\left(\mathrm{m}\right)$

The moon is 384000 km away from earth. How long does it take the light to make the round trip, if a laser beam is sent to the moon and reflected back to the earth by a mirror placed on the moon by an astronaut?

Name the branch of physics which deals with the formation of images by mirrors and lenses.

Cotyledons are also called-

Light travels through a glass plate of thickness $t$ and having refractive index $\mu .$ If $c$ be the velocity of light in vacuum, time taken by the light to travel through this thickness of glass is

Newton postulated his corpuscular theory on the basis of _______.

Assertion: Different colours travel with different speeds in vacuum.

Reason: Wavelength of light depends on refractive index of the medium.

Assertion: Geometrical optics can be regarded as the limiting case of wave optics.

Reason: When the size of the obstacle or opening is very large compared to the wavelength of light then wave nature can be ignored and light can be assumed to be traveling in a straight line.