Group 10Group 10

Name list :Name list :

Group 10Group 10

Name list :Name list :

Chan Ka Yee (3)Chan Ka Yee (3)

Cheuk Yan Yu (8)Cheuk Yan Yu (8)

Huang Hoi Yee (17)Huang Hoi Yee (17)

Lai Wai Shan (21)Lai Wai Shan (21)

•A motion carried through long distance in a material with no single part of the material ever moving far from its equilibrium positive.

•The motion of one part of the system cause a motion of the nearby parts.

What are Traveling Waves?

•A wave is a succession of continuous pulse.

•It may be transverse or longitudinal wave.

What are standing waves?

• produced by the interference of the two traveling waves which travel oppositely with identical frequency

• can be set up by making a wave and arranging for it to be reflected at the borders of the material in which it travels.

Standing Waves - Nodes and Antinodes

• characterized by certain fixed points along the medium which undergo no displacement,like point B in Fig.2,they are called Nodes

• The points of large positive displacement and points of large negative displacement are called Antinodes,like point A in Fig.2

Fig.2

•When the crest of wave A meet the trough of wave B,they will interfere each other destructively,this makes point of no displacement.

•There should be two fixed ends to generate the waves of identical frequencies

• when the waves reached the fixed end,they will reflect and travel back oppositely (Fig.3.1).

Fig.3.1

• If the timing and frequencies are perfect,there should be a destructive or constructive interference.See fig.3

•Standing involve two sources of waves which are generated by two fixed ends and are opposite in directions.

The Differences between travelling waves and standing waves

•Travelling waves involve only one source of wave

• Travelling wave is the movement of particles in the medium when a disturbance is generated.• Standing wave is formed when a travelling wave is reflected by the fixed end.

Fig.4

•Standing waves involve two sources of waves which are generated by two fixed ends and are opposite in directions.

The Differences between travelling waves and standing waves

•Travelling waves involve only one source of wave

•Standing wave: waveform does not change with time.

Travelling wave: waveform changes with time.

•Travelling waves transfer energy from one place to another.But the energy of standing waves is stored at the positions of antinodes.

•As standing waves are formed in a fixed space, its velocity depends only on the property of the medium in the fixed space.• As travelling waves move through a medium, its velocity depends on the property of the medium through which it travels. If the property of the medium changes, its speed changes.

The Similarities between Standing Wave and Travelling Wave

This figure shows the standing waves on slinky

•Both have crest and trough

•Both have energy•Both have wavefronts •Both are repeated motion. (fig.5)•Particles of both wave vibrate

Fig.5