Waves

Question 1

Mechanical Waves

Answer 1

Require a Medium

Examples: Sound, Water

Question 2

Electromagnetic Waves

Answer 2

Don’t require a medium

Examples: Light, microwaves, x-rays

Question 3

Waves

Answer 3

A model for explaining the transfer of energy

Question 4

Medium

Answer 4

A substance or material which carries the wave and is composed of particles that can interact with each other (ex. water, air, wood, etc.)

Question 5

Part of a Wave: Crest

Answer 5

Highest point

Question 6

Part of a Wave: Trough

Answer 6

Lowest point

Question 7

Part of a Wave: Wavelength

Answer 7

Distance between adjacent identical parts of a wave

Question 8

Part of a Wave: Amplitude

Answer 8

Distance from wave equilibrium (starting point) to crest or trough

Question 9

Part of a Wave: Frequency

Answer 9

How often a wave occurs

Question 10

Part of a Wave: Period

Answer 10

Time it takes for one complete wave

Question 11

How can changing the amplitude of a wave impact its frequency and energy?

Answer 11

More waves, more energy (faster)

Amplitude is distance from wave equilibrium to crest of trough

Question 12

Transverse Waves

Answer 12

Source of wave move up and down (perpendicular)

Light

Question 13

Longitudinal Waves

Answer 13

Source of wave moves left to right (parallel)

Sound

Also called compressional waves

Question 14

Velocity

Answer 14

Distance a wave moves per second.

v = λ f
Velocity (v) m/s
Wavelength (λ) m
Frequency ( f ) Hz

Question 15

Relationship between wavelength and frequency

Answer 15

As wavelengths get smaller, frequencies get higher

Question 16

Relationship between frequency and energy (speed)

Answer 16

The higher the frequency, the more energy the wave has (wave speed)

Question 17

What are the effects of interference on wave patterns?

Question 18

Electromagnetic Spectrum

Answer 18

The EM spectrum is the ENTIRE range of EM waves

In order of increasing frequency and decreasing wavelength

left to right, the wavelengths get smaller and the frequencies get higher.

This is an inverse relationship between wave size and frequency.

This is because the speed of ALL EM waves is the speed of light (300,000 km/s).

Question 19

Radio Waves

Answer 19

longest wavelengths 1000s of meters to .001 m
and the lowest frequencies

Used in: RADAR, cooking food, satellite transmissions

Question 20

Infrared Waves (heat)

Answer 20

Have a shorter wavelength .001 m to 700 nm, and therefore, a higher frequency.

Used for finding people in the dark and in TV remote control devices

Question 21

How fast does Light travels compared to sound in air?

Answer 21

Light travels nearly a million times faster than sound in air.
Light and all electromagnetic waves are transverse waves.

Question 22

What is the Visible Light Spectrum order?

Answer 22

ROY G. BV
red
orange
yellow
green
blue
violet

Question 23

Visible light

Answer 23

Wavelengths range from 700 nm (red light) to 30 nm (violet light) with frequencies higher than infrared waves.

Waves in the EM spectrum that humans can see.
Visible light waves are a very small part of the EM spectrum!

Question 24

Ultraviolet Light

Answer 24

Wavelengths range from 400 nm to 10 nm;

the frequency (and therefore the energy) is high enough with UV rays to penetrate living cells and cause them damage.

Although we cannot see UV light, bees, bats, butterflies, some small rodents and birds can.

UV on our skin produces vitamin D in our bodies. Too much UV can lead to sunburn and skin cancer. UV rays are easily blocked by clothing.

Used for sterilization because they kill bacteria.

Question 25

X Rays

Answer 25

Wavelengths from 10 nm to .001 nm.

Rays have enough energy to penetrate deep into tissues and cause damage to cells; are stopped by dense materials, such as bone.

Used to look at solid structures, bones and bridges (for cracks), and for treatment of cancer.

Question 26

Gamma Rays

Answer 26

Carry most energy and have the shortest wavelengths, less than one trillionth of a meter (10-12).

Gamma rays have enough energy to go through most materials easily

Released by nuclear reactions in nuclear power plants, by nuclear bombs, and by naturally occurring elements on Earth.
Sometimes used in the treatment of cancers.