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at microwave frequencies, the power density considered safe for human exposure is 1 (mw/cm 2 ). a radar radiates a wave with an electric field amplitude e that decays with distance as

User Bramat
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Final answer:

To be exposed to a safe intensity, you would need to be approximately 0.451 meters away from the radar unit. The maximum electric field strength at the safe intensity is approximately 3.36 x 10^-3 V/m.

Step-by-step explanation:

To determine the distance at which the intensity of the leaked microwaves would be considered safe, we can use the formula for intensity:

Intensity = Power / (4 * π * r^2)

Plugging in the given values, we have:

1.00 W/m² = 10.0 W / (4 * π * r^2)

Solving for r, the distance from the radar unit, we find:

r = √(10.0 W / (4 * π * 1.00 W/m²)) = √(10.0 / (4 * π)) m = 0.451 m

Therefore, you would need to be approximately 0.451 meters away from the radar unit to be exposed to an intensity considered safe.

To calculate the maximum electric field strength at the safe intensity, we can use the formula:

Electric Field Strength = √(2 * Intensity * μ₀ / c)

Plugging in the given values and the constants for μ₀ (permeability of free space) and c (speed of light), we have:

Electric Field Strength = √(2 * 1.00 W/m² * 4π x 10^-7 T·m/A * 2.998 x 10^8 m/s) = 3.36 x 10^-3 V/m

Therefore, the maximum electric field strength at the safe intensity is approximately 3.36 x 10^-3 V/m.

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