6.) a. What is the Lorentz Force Law?
b. What are the units of frequency? How is it related to time?
c. What is the wave vector, and its units?
d. What is the wave equation?
e. Given, -sin (wt - kx) find the phase velocity that comes from this wave equation. Hint: Should be in units of
length/time.
f. A laser is emitting photons with velocity 0.15c, frequency 50GHz, that is being absorbed by a black body. This
laser emits the photons through a hole of radius 5µm. The photon has E = Emax sin(wt - kx) ŷ and B =
Bmax sin(wt - kx) 2
Find the Poynting vector, what is its units? Find the magnitude at t=1second and x=π/2meters?
What is the intensity of this photon if power supplied is 120Watts?
What is the radiation pressure on the black body surface?
Find Emax and Bmax using their relations to the speed of light and Average intensity found earlier.
Hints: Intensity = Power/Area, Pressure = Intensity/Speed.