On a sunny summer day, the intensity of sunlight at the earth's surface is about 1000 W/m2. What are the peak electric and magnetic fields in this sunlight?

Question

asked Mar 17, 2020 92.8k views

1 Answer

Armen Stepanyan · Answer 1 · 2020-03-21T00:54:24+0000

Answer:

peak value of magnetic field is

B_o = 2.9 * 10^(-6) T

peak value of electric field is

E_o = 868 N/C

Step-by-step explanation:

As we know that the intensity of electromagnetic waves is given by the formula

$I = \epsilon_0 E_(rms)^2 c$

here we have

I = 1000 W/m^2

$\epsilon_0 = 8.85 * 10^(-12)$

c = 3* 10^8

now we have

1000 = (8.85 * 10^(-12))E_(rms)^2(3 * 10^8)

E_(rms) = 614 N/C

now peak value of electric field is given as

$E_o = \sqrt2 E_(rms)$

So the peak value of electric field is given as

E_o = 868 N/C

Now we have relation between electric field and magnetic field as

B_o = (E_o)/(c)

B_o = (868)/(3* 10^8)

B_o = 2.9 * 10^(-6) T