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The equation for energy (E) of a simple ...

The equation for energy (E) of a simple harmonic oscillator, `E = (1)/(2) mv^(2)+(1)/(2)m omega^(2)x^(2)`?, is to be made "dimensionless" by multiplying by a suitable factor, which may involve the constants, m(mass), `omega`(angular frequency) and h(Planck's constant). What will be the unit of momentum and length?

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To make the energy equation of a simple harmonic oscillator dimensionless, we need to find suitable factors involving mass (m), angular frequency (ω), and Planck's constant (h). Let's break down the solution step by step. ### Step 1: Understand the Energy Equation The energy (E) of a simple harmonic oscillator is given by: \[ E = \frac{1}{2} mv^2 + \frac{1}{2} m \omega^2 x^2 \] where \( v \) is the velocity and \( x \) is the displacement. ### Step 2: Identify Dimensions We need to identify the dimensions of each term in the energy equation: - The dimension of mass (m) is \([M]\). - The dimension of velocity (v) is \([L][T^{-1}]\). - The dimension of angular frequency (ω) is \([T^{-1}]\). - The dimension of displacement (x) is \([L]\). ### Step 3: Analyze the Energy Terms 1. For the kinetic energy term \(\frac{1}{2} mv^2\): \[ \text{Dimension} = [M][L^2][T^{-2}] = [M][L^2][T^{-2}] \] 2. For the potential energy term \(\frac{1}{2} m \omega^2 x^2\): \[ \text{Dimension} = [M][T^{-2}][L^2] = [M][L^2][T^{-2}] \] Both terms have the same dimension: \([M][L^2][T^{-2}]\). ### Step 4: Making the Equation Dimensionless To make the energy dimensionless, we can multiply it by a suitable factor that has the inverse dimensions of energy. ### Step 5: Relate Planck's Constant Planck's constant \( h \) has dimensions of: \[ [h] = [M][L^2][T^{-1}] \] We can relate \( h \) to the other quantities. ### Step 6: Find Suitable Factors We need to find a combination of \( m \), \( \omega \), and \( h \) that gives us a dimensionless quantity. 1. The momentum \( p \) is given by: \[ p = mv \] where \( v = \omega r \) (velocity in terms of angular frequency and radius). 2. Thus, \( p = m(\omega r) \). 3. The dimensions of momentum \( p \) are: \[ [p] = [M][L][T^{-1}] \] 4. We can express \( r \) in terms of \( h \) and \( m \) and \( \omega \): \[ r^2 \sim \frac{h}{m \omega} \] Taking the square root gives: \[ r \sim \sqrt{\frac{h}{m \omega}} \] ### Conclusion The unit of momentum is \([M][L][T^{-1}]\) and the unit of length is \(\sqrt{\frac{h}{m \omega}}\).
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