Physics IGCSE Waves Core

PHYSICS PARTIAL 2

WAVES

• Waves transfer energy without transferring matter.

• When describing wave motion, there are several terms which are important to know, including:

o Wavelength
o Frequency
o Period
o Crest (peak)
o Trough
o Amplitude
o Wave speed




WAVELENGTH

• Wavelength is defined as:

The distance from one point on the wave to the same point on the next wave

• The wavelength is given the symbol λ (lambda) and is measured in metres (m)
• The distance along a wave is typically put on the x-axis of a wave diagram


FREQUENCY

• Frequency is defined as:

The number of oscillations in a second

• Frequency is given by the symbol f and is measured in Hertz (Hz)
• 50 Hz = 50 oscillations in 1 s
1
• 𝑓=
𝑇

, PERIOD
• Time taken for 1 complete oscillation

1
• 𝑇=
𝑓


CRESTS & TROUGHS

• A crest, or a peak, is defined as:

The highest point on a wave above the equilibrium, or rest position

• A trough is defined as

The lowest point on a wave below the equilibrium, or rest, positio


AMPLITUDE

• Amplitude is defined as:

The distance from the undisturbed position to the peak or trough of a wave

• It is given the symbol A and is measured in metres (m)
• Amplitude is the maximum or minimum displacement from the undisturbed position


WAVE SPEED

• Wave speed is the speed at which energy is transferred through a medium
• Wave speed is defined as:

The distance travelled by a wave each second

• The equation used to calculate wave speed is explained in the wave equation


THE WAVE EQUATION

• The equation used to calculate wave speed is:


v=fλ

• Where:
• v = wave speed, measured in metres per second (m/s)
• f = wave frequency, measured in hertz (Hz)
• λ = wavelength, measured in metres (m)
• Wave speed is defined as:

The distance travelled by a wave each second