Question
Question: Fill in the blank: The light emanating from a torchlight is _____ (A) Convergent (B) Divergent ...
Fill in the blank: The light emanating from a torchlight is _____
(A) Convergent
(B) Divergent
(C) Parallel
(D) Irregular
Solution
The light coming out of a source tends to form different shapes and follow different patterns depending on the source. A torchlight has a bulb centred on it, and the light escapes from it to illuminate a place.
Complete step by step answer:
Light refers to the electromagnetic radiation that can be easily detected by the human eye. It is imagined to be consisting of a stream of photons or packets of energy that illuminate the path as they travel. Due these massless bundles of energy, light follows particles as well as wavelike behaviour.
The wavelike behaviour of light was put forward and proven by the double slit experiment. Light from two coherent sources passing through very small slits made diffraction patterns at the end screen. This property was thought to only be possessed by waves. Hence, it was a common verdict that light is a wave.
But Einstein discovered the photoelectric emission effect that showed that light is also made of many photons that behave as a particle. Upon focusing light of a fixed wavelength on a piece of metal, the electrons on its surface were excited to higher energy levels. Einstein also received the Nobel Prize in Physics for this discovery. Soon it was confirmed that light is actually both: a wave and a particle.
Since the light from a flashlight comes from a bulb and moves out in all random directions, it is said to be of divergent nature.
Hence, the correct answer is option (B).
Note:
Most of the everyday examples that we encounter of light have light emanating from them in a divergent manner. For example, the light bulb, headlights of a car. But light also converges in some cases, like the convex lens. This property is very useful in correcting eyesight. Light also travels at a speed that is the fastest ever known to man.