Question 83: EM waves

Question

A beam of light travelling along $$X$$-axis is described by the electric field $$E_{y}=900 \sin \omega(\mathrm{t}-x / c)$$. The ratio of electric force to magnetic force on a charge $$\mathrm{q}$$ moving along $$Y$$-axis with a speed of $$3 	imes 10^{7} \mathrm{~ms}^{-1}$$ will be :
(Given speed of light $$=3 	imes 10^{8} \mathrm{~ms}^{-1}$$)

Accepted Answer

Ratio $$ = {{|q\overrightarrow E |} \over {|q\overrightarrow v  	imes \overrightarrow B |}}$$
$$ = {E \over {vB}} = {{{v_{wave}}} \over v}$$
$$\Rightarrow$$ Ratio $$ = {{3 	imes {{10}^8}} \over {3 	imes {{10}^7}}} = 10$$

Answer

1 : 1

Answer

1 : 10

Answer

10 : 1

Answer

1 : 2

EM waves

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