The graph between radiation power P from a li | vedclass

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(D) The radiation power $P$ of a linear antenna is given by $P \propto \frac{l^2}{\lambda^2}$.From the graph,the slope of the line is $\frac{P}{l^2} \

Vedclass · Accepted Answer

$\frac{\lambda_A}{\lambda_B} = \frac{4}{3}$

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(D) The radiation power $P$ of a linear antenna is given by $P \propto \frac{l^2}{\lambda^2}$.From the graph,the slope of the line is $\frac{P}{l^2} \propto \frac{1}{\lambda^2}$.Therefore,$	ext{Slope} \propto \frac{1}{\lambda^2}$,which implies $\lambda \propto \frac{1}{\sqrt{	ext{Slope}}}$.Thus,$\frac{\lambda_A}{\lambda_B} = \sqrt{\frac{	ext{Slope}_B}{	ext{Slope}_A}} = \sqrt{\frac{	an(53^\circ)}{	an(37^\circ)}}$.Using $	an(53^\circ) \approx \frac{4}{3}$ and $	an(37^\circ) \approx \frac{3}{4}$,we get:$\frac{\lambda_A}{\lambda_B} = \sqrt{\frac{4/3}{3/4}} = \sqrt{\frac{16}{9}} = \frac{4}{3}$.

The graph between radiation power $P$ from a linear antenna and the square of the length of the antenna $l^2$ is shown in the figure for two antennas $A$ and $B$. If all other parameters are the same,find the ratio of the wavelengths of $A$ and $B$,i.e.,$\frac{\lambda_A}{\lambda_B}$.

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