SAMPLE QUESTIONS
1. The electric field part of an electromagnetic wave in a medium is represented by
E
_{X} = 0,
E
_{y} = $2.5\frac{N}{C}cos\left [\left (2\pi \times 10^{6 \frac{rad}{m}} \right )t - \left (\pi \times 10^{-2} \frac{rad}{s} \right )x\right ]$
E_{z} = 0. The wave is
a) moving along y direction with frequency 2π × 10
^{6} Hz and wavelength 200m.
b) moving along x direction with frequency 10
^{6} Hz and wavelength 100m
c) moving along x direction with frequency 10
^{6} Hz and wavelength 200 m
d) moving along -x direction with frequency 10
^{6} Hz and wavelength 200 m
2. In a circuit , L, C and R are connected in series with an alternating voltage source of frequency f. The current leads the voltage by 45
^{0} . The value of C is
a) $\frac{1}{2\pi f\left (2\pi fL + R \right )}$
b) $\frac{1}{\pi f\left (2\pi fL + R \right )}$
c) $\frac{1}{2\pi f\left (2\pi fL - R \right )}$
d) $\frac{1}{\pi f\left (2\pi fL + R \right )}$