Electromagnetic Spectrum

Question 1

What is electromagnetic spectrum?

Answer 1

Range of frequencies ranging from low energy radio waves to short wavelength high frequency high energy gamma rays.

Question 2

What causes electromagnetic waves / radiation?

Answer 2

When charge increase/decrease in speed or experience a sudden change in direction.

Question 3

What is a mechanical wave?

Answer 3

Caused by a disturbance or vibration in matter, called a medium.

Question 4

What is a electromagnetic wave?

Answer 4

These waves do not need a medium to propogate and can travel through air, solid material, vacuum of space.

Question 5

Features of Electromagnetic Radiation

Answer 5

• Transfer energy as radiation from the source of the wave to an absorber
• Can travel through a vacuum
• Travel at the same speed through air or in a vacuum

Question 6

Speed of light

Answer 6

3x10^8 m/s

Question 7

What is a transverse wave?

Answer 7

The displacement of the particles is perpendicular at right angles to the wave movement.

Question 8

Examples of transverse waves

Answer 8

Light and water waves

Question 9

What is a longitudinal wave?

Answer 9

Shows areas of compression and rarefaction
Compressions move left to right
Particles move back to front

Question 10

What is a photon

Answer 10

A particle which can also account for electromagnetic radiation. Shorter wavelengths are more like particles not waves.

Question 11

What is quanta?

Answer 11

Discrete bundles of energy within photons

Question 12

Qualities of Quanta

Answer 12

• No mass
• Travel at velocity of light

Question 13

What is Plancks Constant

Answer 13

• Energy comes in discrete steps or packets
• Energy in a photon can be none, 1 or more but nothing inbetween

Question 14

Wave parameters
Peak

Answer 14

Top point of the wave

Question 15

Wave parameters
Trough

Answer 15

Lowest point of the wave

Question 16

Wave parameters
Wavelength

Answer 16

Distance between waves

Question 17

Wave parameters
Amplitude

Answer 17

Max displacement of a wave from its trough position or half distance between trough and peak

Question 18

What is the relationship between frequency and period of waves?

Answer 18

Inversely proportional (as one increases one decreases)

Question 19

What is the relationship between frequency and wavelength

Answer 19

Inversely proportional

Question 20

What is the relationship between wave speed, frequency and wavelength

Answer 20

Directly proportional
(As wave speed and freq increase, so does wavelength)