Q18 of 32 Page 50

The magnetic field of a beam emerging from a filter facing a floodlight is given by

B0 = 12 × 10–8 sin (1.20 × 107 z – 3.60 × 1015 t) T.


What is the average intensity of the beam?


Given


The equation of magnetic field of the beam


B0 = 12 × 10–8 sin (1.20 × 107 z – 3.60 × 1015 t) T


Comparing the given equation with the general equation of magnetic field i.e.



We have,


We know that the average intensity of an electromagnetic wave is given as




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