A helium-neon laser emits a beam of circular cross section with a radius r and a power P.?. (a) Find the maximum electric field in the beam. (Use any variable or symbol stated above along with the following as necessary: μ0 and c ... (b) What total energy is contained in a length of the beam? (Use the following as necessary: P, l, and c.) (c) Find the momentum carried by a length of the beam. (Use the following as necessary: P, l, and c.)

Question

Physics

Taniya Combs

13 November, 13:22

A helium-neon laser emits a beam of circular cross section with a radius r and a power P.?. (a) Find the maximum electric field in the beam. (Use any variable or symbol stated above along with the following as necessary: μ0 and c ... (b) What total energy is contained in a length of the beam? (Use the following as necessary: P, l, and c.) (c) Find the momentum carried by a length of the beam. (Use the following as necessary: P, l, and c.)

+4

Answers (1)

Know the Answer?

Tyree Wall · Answer 1

there is a relation between intensity of light beam and the magnitude of electric field. I = (1/2) c ϵo n E2 = P/π r2 E2 = 2P/c ϵo nπ r2 E = magnitude of electric field n = refractive index of medium μo ϵ0 = 1 / c2

energy = power*time = P * (1m/speed of light) energy = (P∗1m) / c