\(\Rightarrow \quad u=\sqrt{\frac{2 h}{g}} \times g=\sqrt{2 g h}\)

\(\therefore \quad t_{1}=\)time to reach top \(=\frac{u}{g}=\sqrt{\frac{2 h}{g}}\)

\(\therefore \quad H=h+h^{\prime}=2 h\)

\(t_{2}=\) time of fall \(=\sqrt{\frac{2 \times(2 h)}{g}}\)

\(\quad=2 \sqrt{\frac{h}{g}}\)

Total time \(=t_{1}+t_{2}\)

\(\quad=(2+\sqrt{2}) \sqrt{\frac{h}{g}}\)

\(\quad=3.4 \sqrt{\frac{h}{g}}\)