In the circuit shown, the $n: 1$ step-down transformer and the diodes are ideal. The diodes have no voltage drop in forward biased condition. If the input voltage (in Volts) is $V_{s}(t)=10 \sin \omega t$ and the average value of load voltage $V_{L}(t)$ (in Volts) is $2.5 / \pi$, the value of $n$ is $\_\_\_\_\_\_\_$.
- $4$
- $8$
- $12$
- $16$