Answer:
We must be approximately at least 1.337 meters away to be exposed to an intensity considered to be safe.
Explanation:
Let suppose that intensity is distributed uniformly in a spherical configuration. By dimensional analysis, we get that intensity is defined by:
[tex]I = \frac{\dot W}{\frac{4\pi}{3}\cdot r^{3}}[/tex] (1)
Where:
[tex]I[/tex] - Intensity, measured in watts per square meter.
[tex]r[/tex] - Radius, measured in meters.
If we know that [tex]\dot W = 10\,W[/tex] and [tex]I = 1\,\frac{W}{m^{2}}[/tex], then the radius is:
[tex]r^{3} = \frac{\dot W}{\frac{4\pi}{3}\cdot I }[/tex]
[tex]r = \sqrt[3]{\frac{3\cdot \dot W}{4\pi\cdot I} }[/tex]
[tex]r = \sqrt[3]{\frac{3\cdot (10\,W)}{4\pi\cdot \left(1\,\frac{W}{m^{2}} \right)} }[/tex]
[tex]r \approx 1.337\,m[/tex]
We must be approximately at least 1.337 meters away to be exposed to an intensity considered to be safe.