 #1
PhysicsStudy
 6
 0
Homework Statement
Discuss the suitability for generating electricity or directly driving mechanical machinery.
High breast water wheel:
Head/m 4.65
Flow rate*/m3 s−1 1.0
Power/kW 39.4
Diameter/m 7.0
Width or height/m 2.5
Mass/kg 14 143
Powertoweight ratio/W kg−1 2.8
This leads to the following additional data...
Torque = 72572 Nm
Angular momentum = 72572 Nms
Rotational kinetic energy = 60.80 kJ
Victor water turbine:
Head/m 5.55
Flow rate*/m3 s−1 0.8
Power/kW 36.6
Diameter/m 0.76
Width or height/m 0.7
Mass/kg 534
Powertoweight ratio/W kg−1 68.5
This leads to the following additional data...
Torque = 807.5 Nm
Angular momentum = 807.5 Nms
Rotational kinetic energy = 16.91kJ
Homework Equations

The Attempt at a Solution
I'm thinking that a power output of 3540kW (i.e. both of them) is suitable for smallscale electricity generation.
However, to directly drive industrial machinery a high torque and angular momentum would be required, hence only the high breast water wheel is suitable for that task.
There are 6 marks for this question, which seems rather a lot for such handwavery. Can anyone point out what I can do for greater detail, or where my logic may have gone wrong?
Many thanks in advance!