U2.1 Waves

Question 1

What is a Progressive Wave?

Answer 1

A wave that transports energy by causing vibrations in the material or medium through which it moves.

Question 2

What is a transverse wave?

Answer 2

A wave where the vibrations are perpendicular to the direction of travel.
Eg. Electromagnetic waves, Waves on a string.

Question 3

What is a longitudinal wave?

Answer 3

A wave where the vibrations are parallel to the direction of travel.
Eg. Sound, Ultrasound.

Question 4

What is period?

Answer 4

The time it takes a particle in a medium to complete one wave cycle.

Measured in Seconds (s).

Question 5

What is frequency?

Answer 5

The amount complete waves that pass a point in one second or the number of complete oscillations of a particle in the medium in one second.

Measured in Hertz (Hz).

Question 6

What is wavelength?

Answer 6

The distance the wave form progresses in the periodic time.

It is the distance between two consecutive crests or troughs.

Measured in Metres (m).

Question 7

What is amplitude?

Answer 7

The maximum displacement of a particle of the medium from rest.

Measured in Metres (m)

Question 8

What is the equation for frequency.

Answer 8

Frequency = 1 / Period

F = 1/T

Question 9

What is the equation for velocity of a wave

Answer 9

Velocity = Frequency x Wavelength

V = f λ

Question 10

What is the equation for phase difference in degrees?

Answer 10

X x 360º t x 360º
Phase Difference = ————— = —————
λ T

X = the distance between the peaks of two waves
t = the time interval between the two peaks

Question 11

What is polarised and unpolarised light?

Answer 11

Unpolarised light is light that has multiple planes of vibration.

Polarised light only has one plane of vibration.

Question 12

What is the wavelength and frequency of gamma rays?

Answer 12

λ = 10^-12 to 10^-16m

Question 13

In terms of phase difference what does one wave cycle equal?

Answer 13

2π rads = 360º = 1λ

Question 14

What is the wavelength and frequency of X rays?

Answer 14

λ = 10^-9 to 10^-12m

Question 15

What is the wavelength and frequency of UV?

Answer 15

λ = 10^-7 to 10^-9m

Question 16

What is the wavelength and frequency of visible light?

Answer 16

λ = 700 to 400nm

Question 17

What is the wavelength and frequency of IR?

Answer 17

λ = 10^-4 to 10^-6m

Question 18

What is the wavelength and frequency of microwaves?

Answer 18

λ = 10^-1 to 10^-4m

Question 19

What is the wavelength and frequency of radio waves?

Answer 19

λ = 10^-1 to 10^-4m