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One end of a long string of linear mass ...

One end of a long string of linear mass dnesity `8.0xx10^(-3)kgm^(-1)` is connected to an electrically driven tuning fork of frequency 256 Hz. The other end passes over a pulley and is tied to a pan containing a mass of 90 kg. The pulley end absorbs all the incoming energy so that reflected waves at this end have negligible amplitude. At `t=0` the left end (fork end) of the string `x=0` has zero transverse displacement `(y=0)` and is moving along positive y-direction. The amplitude of the wave is 5.0 cm. Write down the transverse displacement y as function of x and t that describest the wave on the string.

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To find the transverse displacement \( y \) as a function of \( x \) and \( t \) for the wave on the string, we will follow these steps: ### Step 1: Identify the Given Values - Linear mass density \( \mu = 8.0 \times 10^{-3} \, \text{kg/m} \) - Frequency \( f = 256 \, \text{Hz} \) - Mass hanging from the string \( m = 90 \, \text{kg} \) - Amplitude \( A = 5.0 \, \text{cm} = 0.05 \, \text{m} \) ### Step 2: Calculate the Tension in the String The tension \( T \) in the string due to the hanging mass is given by: \[ T = mg = 90 \, \text{kg} \times 9.8 \, \text{m/s}^2 = 882 \, \text{N} \] ### Step 3: Calculate the Velocity of the Wave The velocity \( v \) of the transverse wave on the string can be calculated using the formula: \[ v = \sqrt{\frac{T}{\mu}} = \sqrt{\frac{882 \, \text{N}}{8.0 \times 10^{-3} \, \text{kg/m}}} \] Calculating this gives: \[ v \approx \sqrt{110250} \approx 332 \, \text{m/s} \] ### Step 4: Calculate the Angular Frequency \( \omega \) The angular frequency \( \omega \) is given by: \[ \omega = 2\pi f = 2 \times 3.14 \times 256 \approx 1600 \, \text{rad/s} \] ### Step 5: Calculate the Wavelength \( \lambda \) The wavelength \( \lambda \) can be calculated using: \[ \lambda = \frac{v}{f} = \frac{332 \, \text{m/s}}{256 \, \text{Hz}} \approx 1.297 \, \text{m} \] ### Step 6: Calculate the Wave Number \( k \) The wave number \( k \) is given by: \[ k = \frac{2\pi}{\lambda} = \frac{2 \times 3.14}{1.297} \approx 4.84 \, \text{m}^{-1} \] ### Step 7: Write the Equation for Transverse Displacement \( y \) The general form of the wave equation traveling in the positive y-direction is: \[ y(x, t) = A \sin(\omega t - kx) \] Substituting the values we have: \[ y(x, t) = 0.05 \sin(1600 t - 4.84 x) \] ### Final Answer Thus, the transverse displacement \( y \) as a function of \( x \) and \( t \) is: \[ y(x, t) = 0.05 \sin(1600 t - 4.84 x) \]
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