QuestionJuly 5, 2025

The intensity of a laser beam is 450W/m^2 What is the rms value of the electric field of this laser beam? 1.7times 10^5V/m 3.4times 10^5V/m 5.8times 10^2V/m 4.1times 10^2V/m 1.3times 10^3V/m

The intensity of a laser beam is 450W/m^2 What is the rms value of the electric field of this laser beam? 1.7times 10^5V/m 3.4times 10^5V/m 5.8times 10^2V/m 4.1times 10^2V/m 1.3times 10^3V/m
The intensity of a laser beam is 450W/m^2
What is the rms value of the electric field of this laser beam?
1.7times 10^5V/m
3.4times 10^5V/m
5.8times 10^2V/m
4.1times 10^2V/m
1.3times 10^3V/m

Solution
4.7(233 votes)

Answer

580 \, V/m Explanation 1. Use the formula for intensity The intensity I of an electromagnetic wave is given by I = \frac{1}{2} c \epsilon_0 E_{\text{rms}}^2, where c is the speed of light and \epsilon_0 is the permittivity of free space. 2. Rearrange to find E_{\text{rms}} Solve for E_{\text{rms}}: E_{\text{rms}} = \sqrt{\frac{2I}{c \epsilon_0}}. 3. Substitute known values Use I = 450 \, W/m^2, c = 3 \times 10^8 \, m/s, and \epsilon_0 = 8.85 \times 10^{-12} \, C^2/N \cdot m^2. 4. Calculate E_{\text{rms}} E_{\text{rms}} = \sqrt{\frac{2 \times 450}{3 \times 10^8 \times 8.85 \times 10^{-12}}}.

Explanation

1. Use the formula for intensity<br /> The intensity $I$ of an electromagnetic wave is given by $I = \frac{1}{2} c \epsilon_0 E_{\text{rms}}^2$, where $c$ is the speed of light and $\epsilon_0$ is the permittivity of free space.<br />2. Rearrange to find $E_{\text{rms}}$<br /> Solve for $E_{\text{rms}}$: $E_{\text{rms}} = \sqrt{\frac{2I}{c \epsilon_0}}$.<br />3. Substitute known values<br /> Use $I = 450 \, W/m^2$, $c = 3 \times 10^8 \, m/s$, and $\epsilon_0 = 8.85 \times 10^{-12} \, C^2/N \cdot m^2$.<br />4. Calculate $E_{\text{rms}}$<br /> $E_{\text{rms}} = \sqrt{\frac{2 \times 450}{3 \times 10^8 \times 8.85 \times 10^{-12}}}$.
Click to rate:

Similar Questions