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Check the correctness of the equation `y=a"sin"(2pi)/(lamda)(vt-x)` using dimensional analysis where y is the displacement of a particle at a distance x from the origin at time `t, lamda`- wavelength v-wave velocity, a- amplitude.

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To check the correctness of the equation \( y = A \sin\left(\frac{2\pi}{\lambda}(vt - x)\right) \) using dimensional analysis, we will follow these steps: ### Step 1: Identify the dimensions of each term in the equation 1. **Displacement \( y \)**: The dimension of displacement is length, denoted as \([L]\). 2. **Amplitude \( A \)**: The amplitude is also a measure of length, so its dimension is \([L]\). 3. **Wavelength \( \lambda \)**: Wavelength is the distance between two successive crests of a wave, hence its dimension is also \([L]\). 4. **Wave velocity \( v \)**: The dimension of wave velocity is length per time, denoted as \([L T^{-1}]\). 5. **Distance \( x \)**: The dimension of distance is length, denoted as \([L]\). 6. **Time \( t \)**: The dimension of time is denoted as \([T]\). ### Step 2: Analyze the argument of the sine function The argument of the sine function is given by: \[ \frac{2\pi}{\lambda}(vt - x) \] We need to ensure that this entire expression is dimensionless. 1. **Evaluate \( vt \)**: - The dimension of \( vt \) is: \[ [L T^{-1}] \cdot [T] = [L] \] So, \( vt \) has the dimension of length \([L]\). 2. **Evaluate \( vt - x \)**: - Since both \( vt \) and \( x \) have the dimension of length \([L]\), their difference \( vt - x \) also has the dimension of length \([L]\). 3. **Combine with \( \lambda \)**: - Now, we have: \[ \frac{vt - x}{\lambda} \] The dimension of this term is: \[ \frac{[L]}{[L]} = [1] \] This shows that \( vt - x \) divided by \( \lambda \) is dimensionless. 4. **Final evaluation of the sine argument**: - Since \( 2\pi \) is a constant (dimensionless), we have: \[ \frac{2\pi}{\lambda}(vt - x) \text{ is dimensionless.} \] ### Step 3: Conclusion Since the argument of the sine function is dimensionless, and both \( y \) and \( A \) have the dimension of length \([L]\), we can conclude that the left-hand side (LHS) and the right-hand side (RHS) of the equation have the same dimensions. Therefore, the equation is dimensionally correct. ### Final Result The equation \( y = A \sin\left(\frac{2\pi}{\lambda}(vt - x)\right) \) is dimensionally correct. ---

To check the correctness of the equation \( y = A \sin\left(\frac{2\pi}{\lambda}(vt - x)\right) \) using dimensional analysis, we will follow these steps: ### Step 1: Identify the dimensions of each term in the equation 1. **Displacement \( y \)**: The dimension of displacement is length, denoted as \([L]\). 2. **Amplitude \( A \)**: The amplitude is also a measure of length, so its dimension is \([L]\). 3. **Wavelength \( \lambda \)**: Wavelength is the distance between two successive crests of a wave, hence its dimension is also \([L]\). 4. **Wave velocity \( v \)**: The dimension of wave velocity is length per time, denoted as \([L T^{-1}]\). ...
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Knowledge Check

  • A transverse wave is represented by the equation y = y_(0) sin (2pi)/(lambda) (vt-x) For what value of lambda is the particle velocity equal to two time the wave velocity ?

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