For the calculation of Duna's energy, the following data is provided:

cross-sectional velocity

per second at mean water level

in Budapest $\quad 0.8 \mathrm{~m} \quad 3000 \mathrm{~m}^{2}$

at Izlás bank (Alduna) $\quad 3.8 \mathrm{~m} \quad 2000 \mathrm{~m}^{2}$

How many kilograms of water flow through the cross-section per second in Budapest and how many at the Izlás bank? How many horsepower does the energy flowing per second correspond to here and there? Can this energy be utilized in Budapest? At Izlás, a 20-meter drop could be achieved with relatively short channel construction. How many indicated horsepower could be obtained from this site?
Amaz 1044 horsepower, this corresponds to 75000 horsepower capacity. The energy in Budapest cannot be economically utilized, for a 3-meter drop, the amount necessary for wheel or turbine waterworks would require a very long channel to be built. At Izlás with a 20 m drop, $2100000(H P)_{i}$ could be gained.

(Freund Ernó, Budapest.)

The problem was solved by: Bánó L., Csada I., Ehrenstein P., Földes R., Pözel T., Jánosy Gy., Szilas O.