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Homework Help: Electric fields, Pulses, Electromagnetic energy

  1. Mar 12, 2005 #1
    I'm working on these problems can anyone help me with it?

    1. In an EM wave traveling west, the B field oscillates vertically and has a frequency of 56.0 kHz and an rms strangth of 7.90E-9 T. What is the rms strength of the electric field?

    2. Pulsed lasers used for science and medicine produce very short bursts of electromagnetic energy. The laser light wavelength is 1.040 E3 nm, and the pulse lasts for 55 picoseconds. How many wavelengths are found within the laser points? How short would the pulse need to be to fit only one wavelength?

    3. A mirror at an amusement park shows an upright image of any person who stands 1.3 m in front of it. If the image is four times the person's height, what is the radius of the curvature?

    4. The image of a distant tree is virtual and very small when viewed in a curved mirror. The image appears to be 15.0 cm behind the mirror. The mirror is convex. What is the radius of the curvature?
  2. jcsd
  3. Mar 12, 2005 #2
    Nevermind, thanks :) I already have them answered!
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