LT: introduction to light

Question 1

what is light?

Answer 1

visible light is
- a form of energy.
- part of the EM spectrum (electromagnetic spectrum)

Question 2

what does the ray model of light represent and how?

Answer 2

the ray model of light is used to represent the path taken by light.
straight lines represent the paths of light;
arrows represent the direction of light travel

Question 3

define luminous objects

Answer 3

luminous objects emit light on their own (in all directions.)

light travels in straight lines from objects to our eyes, allowing us to see them.

Question 4

define non-luminous objects

Answer 4

non-luminous objects do not emit light on their own.

light from a light source can reflect off these objects and enter our eyes, allowing us to see them.

Question 5

when light is incident on an object, it can undergo…

Answer 5

absorption, reflection, refraction, dispersion

Question 6

what is the principle of reversibility of light?

Answer 6

light will follow exactly the same path if its direction of travel is reversed