Question

Additional Problems A helium-neon laser, radiating at 632.8 $\mathrm{nm}$ , has a power output of 3.0 $\mathrm{mW}$ . The beam diverges (spreads) at angle $\theta=0.17$ mrad (Fig. 33-72). (a) What is the intensity of the beam 40 $\mathrm{m}$ from the laser? (b) What is the power of a point source providing that intensity at that distance?

          Additional Problems
A helium-neon laser, radiating at 632.8 $\mathrm{nm}$ , has a power output of 3.0 $\mathrm{mW}$ . The beam diverges (spreads) at angle $\theta=0.17$ mrad (Fig. 33-72). (a) What is the intensity
of the beam 40 $\mathrm{m}$ from the laser? (b) What is the power of a point source providing that intensity at that distance?

Added by Elizabeth W.

University Physics with Modern Physics

Hugh D. Young 14th Edition

Instant Answer

Solved by Expert Paul Gabriel

12/20/2021

Step 1

Given: Power output, P = 3.0 mW = $3.0 \times 10^{-3}$ W Beam divergence angle, $\theta$ = 0.17 mrad Distance, d = 40 m Intensity, I = $\frac{P}{\pi \theta^2 d^2}$ Substitute the given values: $I = \frac{3.0 \times 10^{-3}}{\pi \times (0.17 \times 10^{-3})^2 Show more…

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Additional Problems A helium-neon laser, radiating at 632.8 $\mathrm{nm}$ , has a power output of 3.0 $\mathrm{mW}$ . The beam diverges (spreads) at angle $\theta=0.17$ mrad (Fig. 33-72). (a) What is the intensity of the beam 40 $\mathrm{m}$ from the laser? (b) What is the power of a point source providing that intensity at that distance?