Key Terms

Prepared by: learnloophq@gmail.com

Last edited 26 days ago by Learn LoopHQ.

Chapter: 06. Light

⁠

Light: It is a form of energy that causes the sensation of vision in us.

Luminous objects: Objects which emit light of their own.

Non-luminous objects: Objects which do not emit light of their own.

Rectilinear propagation of light: The property of light travelling in a straight line.

Pinhole camera: A simple device based on the principle of rectilinear propagation of light.

Real image: An image that can be obtained on a screen.

Virtual image: An image that can be viewed but cannot be obtained on a screen.

Magnification: The ratio of the size of the image to that of the object.

Transparent object: An object through which light can pass completely.

Translucent object: An object through which only a part of the light passes and the rest is absorbed or scattered.

Opaque object: An object through which light does not pass at all; it is either reflected, absorbed or scattered by the object.

Shadow: The dark patch formed behind an opaque object when it is placed in the path of light.

Umbra: The central darkest part of the shadow which does not receive any light from the source.

Penumbra: The region of partial darkness which surrounds the umbra.

Eclipse: The shadow cast by the Earth and the moon.

Solar eclipse: The sun becoming invisible, partly or wholly, when the sun, the moon and the Earth are in a straight line, and the moon lies between the sun and the Earth.

Total solar eclipse: The eclipse that occurs at places on the Earth which fall in the umbra region of the moon’s shadow.

Partial solar eclipse: The eclipse that occurs at places on the Earth which fall in the penumbra region of the moon’s shadow.

Annular solar eclipse: The eclipse that occurs at certain places on the Earth which lie at the tip of the umbra of the moon’s shadow.

Diamond ring: The bright ring that appears in the sky for a very short period of time during annular solar eclipse.

Lunar eclipse: The moon becoming invisible, partly or wholly, when the sun, the Earth and the moon are in a straight line, and the Earth comes in between the sun and the moon.

Total lunar eclipse: The eclipse that occurs when the moon is totally in the umbra region of the Earth’s shadow.

Partial lunar eclipse: The eclipse that occurs when the moon lies partly in the umbra region and partly in the penumbra region of the Earth’s shadow.

Want to print your doc?
This is not the way.

Try clicking the ⋯ next to your doc name or using a keyboard shortcut (

CtrlP

) instead.