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6.1WAVES

DISPLACEMENT -TIME GRAPHDISPLACEMENT DISTANCE GRAPH

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LEARNING OUTCOMES Sketch and interpret a displacement-

time graph for a wave

Sketch and interpret a displacement-

distance ra h for a wave Clarify the relationship between

speed, wavelength and frequency

Solve problems involving speed,

wavelength and frequency

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DISPLACEMENT TIME GRAPH

The motion of an oscillating spring can beplotted on a displacement time graph

O is called the equilibrium position.

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DISPLACEMENT TIME GRAPH

Amplitude, a: The maximum displacement

from its equilibrium position. SI unit: meter (m)

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DISPLACEMENT TIME GRAPH

Period, T : The time for one complete

oscillation Frequency, f:

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DISPLACEMENT DISTANCE GRAPH

a = amplitde

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DISPLACEMENT DISTANCE GRAPH

= wavelength

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1111

Increasing Amplitude,a for displacement time graph

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Increasing Period,T for displacement time graph

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Increasing wavelength, , for displacement time graph

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Example 2

0.02 m

0.4 s1/0.4 = 2.5 Hz

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Example 2

1.2 cm6 cm

25 x 6 = 150 cm/s

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QUESTION 1

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QUESTION 2

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QUESTION 3

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QUESTION 4

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THE RELATIONSHIP BETWEENSPEED, WAVELENGTH AND

FREQUENCY

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The number of ducks passing through, Xevery second is n,

The distance between the ducks is l speed, v = n x l

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Number of ducks passing X per second , number of ducks passing X per second , n frequency of the waves, f Distance between two ducks , l

wavelength, speed ,v = n x l = f

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THE RELATIONSHIP BETWEENSPEED, WAVELENGTH AND

FREQUENCYREQUENCYv = f

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Example 3

Frequency = 50 Hz. Measure thewavelength & calculate the speed ofthe wave.

Wavelength = 2 cm = 0.02 m Speed, v = f = 50 x 0.02 = 1 m/s

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QUESTION 5

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QUESTION 5

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QUESTION 6

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QUESTION 6 - explaination