xavier catholic college physics the world communicates
XAVIER CATHOLIC COLLEGE
PHYSICS
THE WORLD COMMUNICATES
Worksheet 6: • 2.5b
Students : present graphical information, solve problems and analyse information involving superposition of waves
Superposition of Waves When two (or more) sources of vibration each produce a wave in a medium, the waves interfere with each other. The amplitude of the combined wave is equal to the (vector) sum of the amplitudes of the component waves. This process is called superposition and the combination wave is the resultant wave. While waves interfere when they occupy the same positions in a medium, they continue on their respective journeys unaltered, except for the time they interfere. The above is known as the Superposition Principle. Where the waves add together it is known as constructive interference and where they subtract it is referred to as destructive interference. The cartoon of Mr. Waters on one of his fishing expeditions makes this a little clearer.
(Shadwick; 2004: 11)
W6-2.5b-Superposition of Waves.doc
Page 1 of 4
(Shadwick; 2004: 11) W6-2.5b-Superposition of Waves.doc
Page 2 of 4
1. Consider the two pulses travelling towards each other along a string as shown. How will the string appear at the instant the centres of the pulses coincide?
(Moyle et al; 1993: 116)
2. Redraw the two pulses depicted below when the centres of the pulses coincide.
(Moyle et al; 1993: 116)
3. Two wave pulses travel at 10 ms-1 as shown. a. Draw the string 0.20 s later. b. How much time is needed before the pulses look the same shape as they are shown here?
(Moyle et al; 1993: 116)
W6-2.5b-Superposition of Waves.doc
Page 3 of 4
4. The diagram below shows a pair of waves. Superimpose the pair on the same axes.
(Shadwick; 2004: 16)
Acknowledgements Moyle, D., Allan, P. & Millar, G. (1993) A Question of Physics . Port Melbourne, Rigby Heinemann Shadwick, B. (2004) Surfing Physics The World Communicates . Marrickville, SciencePress W6-2.5b-Superposition of Waves.doc
Page 4 of 4
PHYSICS
THE WORLD COMMUNICATES
Worksheet 6: • 2.5b
Students : present graphical information, solve problems and analyse information involving superposition of waves
Superposition of Waves When two (or more) sources of vibration each produce a wave in a medium, the waves interfere with each other. The amplitude of the combined wave is equal to the (vector) sum of the amplitudes of the component waves. This process is called superposition and the combination wave is the resultant wave. While waves interfere when they occupy the same positions in a medium, they continue on their respective journeys unaltered, except for the time they interfere. The above is known as the Superposition Principle. Where the waves add together it is known as constructive interference and where they subtract it is referred to as destructive interference. The cartoon of Mr. Waters on one of his fishing expeditions makes this a little clearer.
(Shadwick; 2004: 11)
W6-2.5b-Superposition of Waves.doc
Page 1 of 4
(Shadwick; 2004: 11) W6-2.5b-Superposition of Waves.doc
Page 2 of 4
1. Consider the two pulses travelling towards each other along a string as shown. How will the string appear at the instant the centres of the pulses coincide?
(Moyle et al; 1993: 116)
2. Redraw the two pulses depicted below when the centres of the pulses coincide.
(Moyle et al; 1993: 116)
3. Two wave pulses travel at 10 ms-1 as shown. a. Draw the string 0.20 s later. b. How much time is needed before the pulses look the same shape as they are shown here?
(Moyle et al; 1993: 116)
W6-2.5b-Superposition of Waves.doc
Page 3 of 4
4. The diagram below shows a pair of waves. Superimpose the pair on the same axes.
(Shadwick; 2004: 16)
Acknowledgements Moyle, D., Allan, P. & Millar, G. (1993) A Question of Physics . Port Melbourne, Rigby Heinemann Shadwick, B. (2004) Surfing Physics The World Communicates . Marrickville, SciencePress W6-2.5b-Superposition of Waves.doc
Page 4 of 4
