Problems on light as radiation
Problem : Compute the energy density of a 2.0 mW laser beam with a diameter of 2mm.
Problem : The power per unit area incident on the earth due to sunlight is about 1.4 kW/m 2 . What is the approximate magnitude of the electric field vector on sunlight near the earth ( μ 0âÉá4Π×10-7 N.s 2 /C 2 )?
Problem : Write an expression (in SI units) for the magnetic field of a 10 MHz light wave traveling in the negative z direction and an electric field amplitude of .
Problem : Consider the following electric and magnetic waves:
Show that these waves satisfy Maxwell's equations in free space. What conditions must be satisfied?
Problem : Consider a 60W light bulb. Assume that all radiation given off is in the form of light of wavelength 650 nm. Calculate the number of photons given off per second.