A linearly polarized microwave of wavelength 1.49 cm is directed along the posit

Question

A linearly polarized microwave of wavelength 1.49 cm is directed along the positive x axis. The electric field vector has a maximum value of 180 V/m and vibrates in the xy plane. Assume that the magnetic field component of the wave can be written in the form

A linearly polarized microwave of wavelength 1.49 cm is directed along the positive x axis. The electric field vector has a maximum value of 180 V/m and vibrates in the xy plane. Assume that the magnetic field component of the wave can be written in the form B = Bmax sin (kx ? ?t). Find Bmax. Find k. Find ?. Calculate the average value of the Poynting vector for this wave. If this wave were directed at normal incidence onto a perfectly reflecting sheet, what radiation pressure would it exert? What acceleration would be imparted to a 455-g sheet (perfectly reflecting and at normal incidence) with dimensions of 1.00 m times 0.750 m?

Explanation / Answer

Em/Bm = c

Bm = Em/c =180/3*10^8 =60*10^-8 T

k=2*pi/lambda = 2*pi/0.0149 =421.69 m^-1

lambda = C*T = C/F

F = C/lambda = 3*10^8/0.0149 =2.0134*10^10 s^-1

H = B/mu

S = 1/2*(E x H)=1/2(Em*B/mu) =0.5*(180*60*10^-8/4*pi*10^-7) =5.4*10^-5/4*pi*10^-7 =

= 42.971 W/m^2

P = S/c =42.971/3*10^8 =1.432*10^-7 N/m^2 =143.239 nPa

A =0.75 m^2

F = P*A =1.074*10^-7 N

a =F/m =2.361*10^-7 m/s/s =236.109 nm/s/s

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.