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By using (i) Newton's formula and (ii) Laplace's formula, calculate the speed of sound in air at standard pressure and temperature. The density of air is `1.293` `kg//m^(3)`. `gamma` = 1.4 for air.

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To calculate the speed of sound in air at standard pressure and temperature using both Newton's formula and Laplace's formula, we can follow these steps: ### Step 1: Using Newton's Formula 1. **Identify the formula**: According to Newton's formula, the speed of sound \( v \) is given by: \[ v = \sqrt{\frac{P}{\rho}} \] where \( P \) is the pressure and \( \rho \) is the density of the medium. 2. **Substitute the values**: - Given: - Pressure \( P = 1.013 \times 10^5 \, \text{N/m}^2 \) (1 atmospheric pressure) - Density \( \rho = 1.293 \, \text{kg/m}^3 \) - Plugging in the values: \[ v = \sqrt{\frac{1.013 \times 10^5}{1.293}} \] 3. **Calculate**: - First, calculate the fraction: \[ \frac{1.013 \times 10^5}{1.293} \approx 78316.5 \] - Now take the square root: \[ v \approx \sqrt{78316.5} \approx 280 \, \text{m/s} \] ### Step 2: Using Laplace's Formula 1. **Identify the formula**: According to Laplace's formula, the speed of sound \( v \) is given by: \[ v = \sqrt{\frac{\gamma P}{\rho}} \] where \( \gamma \) is the adiabatic index (ratio of specific heats). 2. **Substitute the values**: - Given: - \( \gamma = 1.4 \) - Pressure \( P = 1.013 \times 10^5 \, \text{N/m}^2 \) - Density \( \rho = 1.293 \, \text{kg/m}^3 \) - Plugging in the values: \[ v = \sqrt{\frac{1.4 \times 1.013 \times 10^5}{1.293}} \] 3. **Calculate**: - First, calculate the numerator: \[ 1.4 \times 1.013 \times 10^5 \approx 1.4192 \times 10^5 \] - Now calculate the fraction: \[ \frac{1.4192 \times 10^5}{1.293} \approx 109749.7 \] - Now take the square root: \[ v \approx \sqrt{109749.7} \approx 331 \, \text{m/s} \] ### Final Answers - Speed of sound using Newton's formula: \( v \approx 280 \, \text{m/s} \) - Speed of sound using Laplace's formula: \( v \approx 331 \, \text{m/s} \)
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