Question 120: EM waves

Question

The magnetic field of a plane electromagnetic wave is
$$\overrightarrow B  = 3 	imes {10^{ - 8}}\sin \left[ {200\pi \left( {y + ct} ight)} ight]\widehat i$$ T
where c = 3 $$ 	imes $$ 108
 ms–1 is the speed of light.
The corresponding electric field is :

Accepted Answer

Given, $$\overrightarrow B  = 3 	imes {10^{ - 8}}\sin \left[ {200\pi \left( {y + ct} ight)} ight]\widehat i$$ T
$$ 	herefore $$ E
0
= CB
0
= 3 ÃÂ 10
8
ÃÂ 3 ÃÂ 10
Ã¢ÂÂ8
= 9 V/m
We know, $$\left( {\overrightarrow E  	imes \overrightarrow B } ight)||\overrightarrow C $$
And here $$\widehat B = \widehat i\& \widehat C =  - \widehat j$$
$$ 	herefore $$ $$\widehat E =  - \widehat k$$
So, $$\overrightarrow E  =  - 9\sin \left[ {200\pi \left( {y + ct} ight)} ight]\widehat k$$ V/m

Answer

$$\overrightarrow E  =  - {10^{ - 6}}\sin \left[ {200\pi \left( {y + ct} \right)} \right]\widehat k$$ V/m

Answer

$$\overrightarrow E  =  - 9\sin \left[ {200\pi \left( {y + ct} \right)} \right]\widehat k$$ V/m

Answer

$$\overrightarrow E  = 9\sin \left[ {200\pi \left( {y + ct} \right)} \right]\widehat k$$ V/m

Answer

$$\overrightarrow E  = 3 	imes {10^{ - 8}}\sin \left[ {200\pi \left( {y + ct} ight)} ight]\widehat k$$

EM waves

The magnetic field of a plane electromagnetic wave is $\overrightarrow B = 3 \times {10^{ - 8}}\sin \left[ {200\pi \left( {y + ct} \right)} \right]\widehat i T where c = 3 \times $ 108 ms–1 is the speed of light. The corresponding electric field is :

Choose the correct answer: