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The permittivity and permeability of fre...

The permittivity and permeability of free space are `epsilon_(0) = 8.85 xx 10^(-12)C^(2)N^(-1)m^(-2)"and"mu_(0) = 4pi xx 10^(-7)"TmA"^(-1),` respectively. Find the velocity of the electromagnetic wave.

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To find the velocity of electromagnetic waves in free space, we can use the formula: \[ c = \frac{1}{\sqrt{\mu_0 \epsilon_0}} \] where: - \( c \) is the speed of light in vacuum (or the velocity of electromagnetic waves), - \( \mu_0 \) is the permeability of free space, - \( \epsilon_0 \) is the permittivity of free space. ### Step-by-Step Solution: 1. **Identify the values of permittivity and permeability**: - Given: \[ \epsilon_0 = 8.85 \times 10^{-12} \, \text{C}^2 \text{N}^{-1} \text{m}^{-2} \] \[ \mu_0 = 4\pi \times 10^{-7} \, \text{TmA}^{-1} \] 2. **Substitute the values into the formula**: - We need to calculate \( \mu_0 \epsilon_0 \): \[ \mu_0 \epsilon_0 = (4\pi \times 10^{-7}) \times (8.85 \times 10^{-12}) \] 3. **Calculate \( \mu_0 \epsilon_0 \)**: - First, calculate \( 4\pi \): \[ 4\pi \approx 12.5664 \] - Now multiply: \[ \mu_0 \epsilon_0 = 12.5664 \times 10^{-7} \times 8.85 \times 10^{-12} \] \[ \mu_0 \epsilon_0 \approx 1.113 \times 10^{-18} \, \text{Tm}^2\text{C}^2\text{N}^{-1}\text{m}^{-2} \] 4. **Calculate the square root of \( \mu_0 \epsilon_0 \)**: - Now, find the square root: \[ \sqrt{\mu_0 \epsilon_0} = \sqrt{1.113 \times 10^{-18}} \approx 1.054 \times 10^{-9} \] 5. **Calculate the velocity \( c \)**: - Finally, substitute back into the formula for \( c \): \[ c = \frac{1}{\sqrt{\mu_0 \epsilon_0}} \approx \frac{1}{1.054 \times 10^{-9}} \approx 2.997 \times 10^{8} \, \text{m/s} \] ### Conclusion: The velocity of electromagnetic waves in free space is approximately: \[ c \approx 3.00 \times 10^{8} \, \text{m/s} \] ---
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