A) \[\vec{B}=2\times {{10}^{7}}\sin (0.5\times {{10}^{3}}z+1.5\times {{10}^{11}}t)\hat{i}\]
B) \[\vec{B}=2\times {{10}^{-7}}\sin (1.5\times {{10}^{2}}x+0.5\times {{10}^{11}}t)\hat{j}\]
C) \[\vec{B}=2\times {{10}^{-7}}\sin (0.5\times {{10}^{3}}z-1.5\times {{10}^{11}}t)\hat{i}\]
D) \[\vec{B}=60\sin (0.5\times {{10}^{3}}x+1.5\times {{10}^{11}}t)\hat{k}\]
Correct Answer: C
Solution :
Magnetic field when electromagnetic wave propagates in +z direction \[B={{B}_{0}}\sin (kz-\omega t)\] where \[{{B}_{0}}=\frac{60}{3\times {{10}^{8}}}=2\times {{10}^{-7}}\] \[k=\frac{2\pi }{\lambda }=0.5\times {{10}^{3}}\] \[\omega =2\pi f=1.5\times {{10}^{11}}\]You need to login to perform this action.
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