Hoover Dam, Named after President Herbert Hoover, is located 30 miles (48 km) southeast of Las Vegas, Nevada. It is a concrete arch-gravity dam in the Black Canyon of the Colorado River, on the border...

Hoover Dam, Named after President Herbert Hoover, is located 30 miles (48 km) southeast of Las Vegas, Nevada. It is a concrete arch-gravity dam in the Black Canyon of the Colorado River, on the border between the U.S. states of Arizona and Nevada. When completed in 1936, it was both the world's largest electric-power generating station and the world's largest concrete structure. The dam is 379 meters long and 221 meters high. Water flowing from Lake Mead through the gradually-narrowing penstocks to the powerhouse reaches a speed of about 85 miles per hour (140 km/h) by the time it reaches the turbines. There are 17 generators installed (upgraded in 1986-1993) with approximate power output of 4 billion KWh per year. Assume the average total flow rate of the river is 600 m3 /s, calculate the electric power output for the generators that have 92% of conversion efficiency from hydrodynamic energy to electric energy. Compare your calculation to the claimed 4 billion KWh per year. (Hint: use the Bernoulli equation to convert the flow velocity (140 km/hr) to the height of the water assuming 100% efficiency from hydraulic potential to dynamic energy.)