Question

A laser emits a narrow beam of light. The radius of the beam is 1.5 mm, and the power is 1.9 mW. What is the intensity of the laser beam?

Answer 1

Answer: 268.80 W/m^2

Explanation:

Intensity = Power/Area

first convert radius to meters

1.5mm= 1.5x10^-3m

area= pi (1.5x10^-3)^2

= 7.069m^2

convert power to W

1.9mW= 1.9x10^-3W

plug into intensity formula

(1.9x10^-3)/(7.069) = 268.80 W/m^2