A $50 \text{ Hz}$ generating unit has H-constant of $2 \text{ MJ/MVA}$. The machine is initially operating in steady state at synchronous speed, and producing $1 \:pu$ of real power. The initial value of the rotor angle $\delta$ is $5^ \circ$, when a bolted three phase to ground short circuit fault occurs at the terminal of the generator. Assuming the input mechanical power to remain at $1 \: pu$, the value of $\delta$ in degrees, $0.02$ second after the fault is _________.
