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cowgiljl
Dec13-03, 10:56 AM
a waterfall is 30 m high and 10000 kg of water flow over it every second
A) calculate the potential energy
PE = mgh
got 2.94E6 joules

B) calculate the power delevered by the water of all the potential energy is converted to work

F = mA
F= 10000 * 9.80
f = 98000

w = Fm
w 98000 * 10000
w = 980 MJ mega joules

C)If all the power were converted to electricity, how many 100watt light bulbs could be lit

not even sure on how to approach this
[?]

himanshu121
Dec13-03, 11:23 AM
B is WRONG Look at the physicsl dimensions when u multiply force by mass is it Energy

himanshu121
Dec13-03, 12:15 PM
Look the energy mgh which u calulated is per second
which is power itself

with this energy u can lit mgh/100 bulbs

hope u will get now