The intensity of the light is 49.6 W/m²
Explanation:
Given:
Power, P = 1.6mW
P = 0.0016 watt
Diameter, d = 3.5mm
radius, r = 3.5 / 2 = 1.75 mm
r = 1.75 X 10⁻³ m
Area of sphere = 4πr²
A = 4 X 3.14 X ( 1.75 X 10⁻³)²
A = 38.465 X 10⁻6 m²
We know:
Intensity, I = Power / Area
[tex]I = \frac{0.0016}{38.465 X 10^-^6} \\\\I = \frac{1600}{38.465} \\\\I = 49.6 W/m^2[/tex]
Therefore, the intensity of the light is 49.6 W/m²
