--%>
Assignment Help - homework help

calculate the intensity I along y axis

As shown in the figure below, a source at S is sending out a spherical wave:

E1=(A×D/r) cos(wt-2πr/λ); where r is the distance to source S. In addition, there is another plane wave propagating along x axis: E2=Acos(wt-2πx/λ). 

These two waves both projected on a vertical screen as shown in the figure. Please calculate the intensity I along y axis (I should be a function of y, the distance from x axis). D is the distance between the screen and the source.

 

381_optics.png

Hint: For a wave E=E0cos (wt + q), I = 2 = E02. Also r = (D2 + y2)1/2.

For k<<1,  (1+k2)1/2» 1+k2/2.   cosA+cosB = 2cos[(A+B)/2] cos[(A-B)/2]

   Related Questions in Physics

  • Q : Define Hoop conjecture Hoop conjecture

    Hoop conjecture (K.S. Thorne, 1972): The conjecture (as so far unproven, although there is substantial proof to support it) that a non-spherical object, non-spherically compressed, will only form a black hole whenever all parts of the

    		•
  • Q : Explain BCS theory BCS theory -  The

    BCS theory - The theory put forth to elucidate both superconductivity and super fluidity. This suggests that in the superconducting (or super fluid) state electrons form Cooper pairs, where two electrons proceed as a single unit. This takes a non

    		•
  • Q : Explain Rayleigh-Jeans law

    Rayleigh-Jeans law: For a blackbody at the thermodynamic temperature T, the radiance R over a range of frequencies between the nu and nu + dnu is specified by: R = 2 pi nu2 k T/c2.<

    		•
  • Q : Define Heat pumps Heat pumps move heat

    Heat pumps move heat from one place to another. They work similar to refrigeration. The movement of heat takes energy, either electrical energy as in the use of  vapor compression heat pumps or thermal energy as in the use of absorption heat pump

    		•
  • Q : Define Copernican principle Copernican

    Copernican principle (N. Copernicus): The idea, recommended by Copernicus, that the Sun, not the Earth, is at the center of the earth. We now know that neither idea is accurate (that is, the Sun is not even situated at the center of o

    		•
  • Q : Rest mass energy of the electron What

    What do you mean by the rest mass energy of the electron?

    		•
  • Q : Define the term wave fronts What do you

    What do you mean by the term wave fronts? Explain in short.

    		•
  • Q : Define Weber or SI unit of magnetic flux

    Weber: Wb (after W. Weber, 1804-1891): The derived SI unit of magnetic flux equivalent to the flux that, connecting a circuit of one turn, generates in it an electromotive force of 1 V as it is decreased to zero at a uniform rate in a period of 1 s; i

    		•
  • Q : Black-hole dynamic laws or laws of

    Explain  laws of black-hole dynamics or First law of black hole dynamics and Second law of black hole dynamics? 

    Q : What is Wiens displacement law constant

    Wien's displacement law constant, b: It is the constant of Wien displacement law. This has the value of 2.897 756 x 10-3 m K.

    		•