Question

Please answer questions 2 and 3. I solved number 1

An electromagnetic wave from a wire antenna travels (from the reader) toward the plane of the paper. At time t = 0.0 s it strikes the paper at normal incidence. At point O and t = 0.0 s, the magnetic field vector has its maximum value, 4.24×10^-8 T, pointing in the negative y-direction. The frequency of this wave is 1.28×10⁶ Hz.
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1.)What is the x-component of the associated electric field E at time t = 0.0 s? (Use the right-hand rule to determine the direction of E, and hence the sign of the x-component.)
The answer is 1.27×10¹ V/m

2.)What is the magnitude of the Poynting vector of the wave at time t = 0.0 s?

3.)What is the y component of the magnetic field at point O at time 3.91×10^-7 s?

Answer 1

Electric field (3x10P m/s)(4.24x10* T) -1.27x101 V/m As the wave is traveling into the page, the intensity (or Poynting vector is also into the page. Poynting vector, S- Ex B As the direction of wave towards plane and magnetic field down the page the electric should be along x-direction Magitude of poyinting vector: ЕВ На (1.27x10 Vin)(424x10-8T) 4π× 10 0.429 W/m Calculate the number of periods elapsed in the time given T" The number of periods that have passed by in timet T" Now use the sine graph B = B sin (kx-at As you the original magnitude and direction of Bpek, it is easy to calculate what the graph of sine looks like after N periods have passed peak