Light and sound - KS3

Wavelength

The distance between two corresponding parts of a wave

Frequency

Number of cycles per second, measured in Hertz (Hz)

Amplitude

the maximum displacement of a periodic wave

Speed of a wave,c

High Frequency: Low wavelength

Low Frequency: High wavelength

Transverse Wave

a wave vibrating at right angles to the direction of its propagation. Examples: Light, Water waves.

Longitudinal Waves

a wave in which the particles move parallel to the path of the wave. Sound.

Pitch

Perception of the frequency of a sound. High pitch = High Frequency

Laws of reflection

1) angle of incidence= angle of reflection

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2) Incident ray, reflected ray and normal all lie on the same plane

Laws of refraction

1. The incident, normal and refracted ray all lie on the same plane.

EM Wave

A type of wave, such as a light wave or radio wave.

ray diagram

Diffuse reflection

A reflection that occurs when light bounces off an object at different angles. The result is a fuzzy image.

Refraction

The change in speed and direction of light when it passes from one kind of material to another.

period of a wave

Time taken for one complete oscillation. T = 1/f. Units: seconds or s

sound intensity

the energy of the sound wave

Differences between light and sound waves:

1. Light is a transverse wave sound is a longitudinal wave.

2. The speed of Light is much faster than sound. light 300,000,000 m per s. Sound 340 m per s.

3. Sound requires a medium to travel through.