$\begin{matrix}\theta =0 & , & \left| \overline{\varepsilon } \right|  \\\end{matrix}=\left| -N\frac{\Delta \Phi }{\Delta t} \right|=\left| -NA\,\operatorname{Cos}\,\theta \,\frac{\Delta B}{\Delta t} \right|\Rightarrow \left| \overline{\varepsilon } \right|=\left| -100\times 40\times {{10}^{-4}}\times \operatorname{Cos}\,0\times 0/5 \right|\Rightarrow \left| \overline{\varepsilon } \right|=0/2V$