BGS - 08. Waves

Question 1

Transverse and Longitudinal Waves

Transverse waves
Oscillate at right angles to the direction of travel and energy transfer

Longitudinal Waves
Oscilate in the same direction as they travel

Answer 1

2

Question 2

Amplitude, Wavelength and Frequency

Amplitude
is the distance from the maximum disturbance to its undisturned position

Wavelength
is the distance travelled by the wave in on complete cycle

Frequency
A measure of how many waves are produced over a period of time.
Unit of measurements is the Hertz (Hz)
1 Hz = 1 Wave per 1 Second

Answer 2

DIAGRAM

3

Question 3

Amplitude, Wavelength and Frequency

Increase Wavelength = Decrease Frequency

Decrease Wavelength = Increase Frequency

Answer 3

3

Question 4

Wavespeed

The speed a wave travels is related to its wavelength and frequency

Increase wavelength = Decrease Frequency
Decrease wavelength = Increase Frequency

V = f x λ

Answer 4

V = f x λ

v = wave speed
f = frequency
λ = wavelength

If V = 6
f = 3 then λ must equal 2
However, if we increase λ to 3, then f now must now equal 2 for V to equal 6

4

Question 5

Refraction

Using a light wave as example;

If a wave crosses a flat boundary i.e. glass, at right angles i.e. 90° to the glass surface, the wave remains uneffected by the change of speed in experiences passing through a more dense material.

If the wave corsses at any other angle i.e. any other ‘angle of incidence’, the direction changes towards the ‘normal’ 90° of incidence

Answer 5

REFRACTION

4

Question 6

Diffraction

When a waves passes through a gap, on the other side the wave will continue to spread out. How much depends on the relationship between the size of the gap and the wavelength

Answer 6

Significant diffraction
If wavelength and gap are of similar magnitude i.e. same size

Slight DIffraction
If wavelength and gap are different in sizes

5

Question 7

Reflection

The angle of incidence always quals the angle of reflection

Answer 7

REFLECTION

6

Question 8

Sound Waves

Longitudinal waves that must pass through a substance
(Solid, Liquid, Gass)

Volume depends on its amplitude.

Answer 8

Greater the amplitude = Louder the sound
Lower the amplitude = Quieter the sound

7

Question 9

Sound Waves

Human ear can hear sounds within the range of

20 Hz to 20 kHz

Answer 9

Audible range reduces with age

7

Question 10

Sound Waves

The pitch of the sound depends on its frequency

Answer 10

Higher frequency = Higher the sounds pitch

Lower frequency = Lower the sounds pitch

7

Question 11

Electromagnetic Spectrum

As you move through the electromagnetic spectrum from radio waves to gamma radiation, the energy and frequency steadily increase and the wavelengths shorten

Radio = Long wavelength, low frequency
Gamma Radiation = Short wavelength, high frequency

Answer 11

Electromagnetic Spectrum

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