A radar sends an electromagnetic signal of electric field (E0) = 2.25 V/m and magnetic field (B0) = 1.5 $\times$ 10$-$8 T which strikes a target on line of sight at a distance of 3 km in a medium. After that, a part of signal (echo) reflects back towards the radar with same velocity and by same path. If the signal was transmitted at time t = 0 from radar, then after how much time echo will reach to the radar?
Solution
<p>E<sub>0</sub> = 2.25 V/m</p>
<p>B<sub>0</sub> = 1.5 $\times$ 10<sup>$-$8</sup> T</p>
<p>$\Rightarrow {{{E_0}} \over {{B_0}}} = 1.5 \times {10^8}$ m/s</p>
<p>$\Rightarrow$ Refractive index = 2</p>
<p>Distance to be travelled = 6 km</p>
<p>Time taken $= {{6 \times {{10}^3}} \over {1.5 \times {{10}^8}}} = 4 \times {10^{ - 5}}$ s</p>
About this question
Subject: Physics · Chapter: Electromagnetic Waves · Topic: Properties of EM Waves
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