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A wave traveling in a string in the positive x direction has a wavelength of 35 cm, an amplitude of 8.4 cm, and a period of 1.2 s. what is the wave equation (in base si units) that correctly describes this wave? a wave traveling in a string in the positive x direction has a wavelength of 35 cm, an amplitude of 8.4 cm, and a period of 1.2 s. what is the wave equation (in base si units) that correctly describes this wave? y(x,t)=0.084 sin(18x−5.2t) y(x,t)=0.084 sin(0.35x+1.2t) y(x,t)=0.084 sin(2.9x−0.83t) y(x,t)=0.084 sin(18x+5.2t) y(x,t)=0.084 sin(0.35x−1.2t)

User Brpaz
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2 Answers

3 votes

Final answer:

The correct wave equation which describes the wave with given amplitude, wavelength, and period in base SI units is y(x,t) = 0.084 sin(18x−5.2t).

Step-by-step explanation:

The wave traveling in the string in the positive x direction, with a wavelength of 35 cm, an amplitude of 8.4 cm, and a period of 1.2 s, can be described using a sinusoidal wave equation. To convert to base SI units, we must have wavelength λ in meters (m), amplitude A in meters (m), and the period T in seconds (s). Using the wave equation y(x, t) = A sin(kx - ωt + φ), where k is the wave number (2π/λ) and ω is the angular frequency (2π/T), we can calculate the correct constants.

First, we convert the amplitude to meters: 8.4 cm = 0.084 m. Next, we convert the wavelength to meters: 35 cm = 0.35 m. Then, we calculate k = 2π/0.35 m⁻¹, and ω = 2π/1.2 s⁻¹. Inserting these values into the wave equation gives us: y(x, t) = 0.084 sin(2π/0.35 x - 2π/1.2 t), which simplifies to y(x, t) = 0.084 sin(18 x - 5.2 t). Therefore, the correct wave equation in base SI units that describes this wave is y(x,t) = 0.084 sin(18x−5.2t).

User Chris Laarman
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5.7k points
5 votes
The correct answer is
y(x,t)=0.084 sin(18x-5.2t)
Let's see why.

For a wave travelling in the positive x-direction, the wave equation can be written as

y(x,t) =A \sin (kx-\omega t)
where
A is the amplitude

k= (2 \pi)/(\lambda) is the wave number

\omega = (2 \pi)/(T) is the angular frequency

The wave in our problem has an amplitude of

A=8.4 cm = 0.084 m
A wave number of (the wavelength is
\lambda=35 cm = 0.35 m )

k= (2 \pi)/(\lambda)= (2 \pi)/(0.35 m)= 18 m^(-1)
and an angular frequency of (the period is T=1.2 s)

\omega = (2 \pi)/(T)= (2 \pi)/(1.2 s)=5.2 s^(-1)

So, if we put this numbers into the equation, we find (in SI units):

y(x,t)=(0.084) \sin (18 x - 5.2 t)
User Pavan Tiwari
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