**1. The problem statement, all variables and given/known data**

A Little power Station uses the water of a Creek. Per second 10 Liters of water fall from a height of 100 meters on the turbine of a power Station. A direct current I = 10 A ist produced. Find the voltage if the Efficiency of the electricity production is 100 %.

**2. Relevant equations**

The solution is: 1000 V

**3. The attempt at a solution**

10 l / s = 10 kg / s

v = J / C

C = 10 C/s

J = ???

**How can I calculate the Joule? **

Thanks in advance!

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