An 8.0-mW laser beam emits a cylindrical beam of ...

[nevelica]

An 8.0-mW laser beam emits a cylindrical beam of single-wavelength sinusoidal light 0.90 mm in diameter. What is the rms value of the electric field in this laser beam?
 
  (0 = 8.85  10-12 C2/N  m2, 0 = 4  10-7 T  m/A, c = 3.0  108 m/s)
  A) 2200 N/C
  B) 1000 N/C
  C) 1100 N/C
  D) 4100 N/C
  E) 2000 N/C

Question 2

The magnitude of the magnetic field that a long and extremely thin current-carrying wire produces at a distance of 3.0 m from the center of the wire is 2.0  10-3 T. How much current is flowing through the wire? (0 = 4  10-7 T  m/
 
  A)
  A) 30 mA
  B) 190 mA
  C) 19 mA
  D) 380 mA

[bigsis44]

Answer to Question 1

A

Answer to Question 2

A

[nevelica]

Excellent

[tkempin]

Gracias!