- #1
songoku
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Homework Statement
The figure shows water waves traveling between two points P and Q, 20.0 cm apart. A dust particle on the water surface makes 5 complete oscillations in 2.0 s.
What is :
i. The amplitude;
ii. The wavelength;
iii. The frequency;
iv. The speed of the waves ?
Homework Equations
[tex]v=\lambda f[/tex]
The Attempt at a Solution
i. amplitude = 4 cm
ii. I don't understand the question. The question states that "A dust particle on the water surface makes 5 complete oscillations" and I think there should be 5 waves, but in the picture there are only 2.5 waves.
The answer on the book is 8 cm. I guess it's from [tex]\lambda=\frac{20}{2.5}[/tex]
But the answer for frequency is 2.5 Hz. I guess it's from [tex]f=\frac{5\;\text{waves}}{2\;s}[/tex]
So I confused whether there are 2.5 waves or 5 waves.
Thanks