Due to presence of an em-wave whose electric component is given by \( E = 100 \sin (\omega t - k x) \, \mathrm{N\,C}^{-1} \), a cylinder of length \( 200 \, \text{cm} \) holds certain amount of em-energy inside it. If another cylinder of same length but half diameter than previous one holds same amount of em-energy, the magnitude of the electric field of the corresponding em-wave should be modified as:
