Light

Question 1

Light

Answer 1

Light is a form of energy that travels in waves through empty space and materials

Question 2

Electromagnetic waves carry both ____ and _____ energy.

Answer 2

Magnetic, electrical

Question 3

Electromagnetic radiation can be described in terms of a stream of massless articles, called _____, each travelling in a wave-like pattern at the speed of light.

Answer 3

photons

Question 4

Frequency

Answer 4

The number of crests that pass a given point within one second

Question 5

Wavelength

Answer 5

The distance between crests

Question 6

Crests

Answer 6

A crest is a point on a surface wave where the displacement of the medium is at a maximum.

Question 7

Trough

Answer 7

the portion of a wave, such as a light wave, in which the amplitude lies below its average value.

Question 8

Energy

Answer 8

An electromagnetic wave can also be described in terms of its energy - in units of electron volts (eV)

Question 9

eV

Answer 9

Electron volts

Question 10

Types of electromagnetic waves, order in longest to shortest

Answer 10

Radio waves, microwaves, infrared radiation, visible light, UV radiation, X-rays, gamma rays

Question 11

Moving along the spectrum from long to short wavelengths, energy ______ as the wavelength shortens.

Answer 11

increases

Question 12

Incandescence

Answer 12

Light energy given off by an object because it is very hot

Question 13

Luminescence

Answer 13

Light energy given off without a heat source

Question 14

Flourescence

Answer 14

Light emitted during exposure of the source to ultraviolet light, but only when the energy source is present

Question 15

Phosphorescence

Answer 15

Light emitted during exposure of the source to ultraviolet light, even after the source is removed

Question 16

Chemiluminescence

Answer 16

Light energy produced by a chemical reaction

Question 17

Bioluminescence

Answer 17

Light energy produced by a biochemical reaction in a living organism

Question 18

Reflection

Answer 18

Process in which light “bounces off” the surface of an object and travels in another direction.

Question 19

Specular (Regular) Reflection

Answer 19

Reflection of light off a smooth shiny surface

Question 20

Diffuse Reflection

Answer 20

Reflection of light off a bumpy, rough, surface

Question 21

Absorbtion

Answer 21

Process in which light energy remains in the object that it hits, and the light energy is converted into heat.

Question 22

Transmission

Answer 22

Process in which light travels through an object and continues travelling upon exiting the object

Question 23

Light from the sun

Answer 23

• Most abundant source of light
• Hydrogen atoms in the sun collide and sometimes form helium
• Energy is released in the form of light

Question 24

Emission of light

Answer 24

When electrons collide with other atoms, this causes the outer electrons to get pushed to a higher level. When the electron returns to the lower energy level, the energy difference is given off as a photon of light. (Electromagnetic radiation)