Answer:
Q = 913.9 gpm
Explanation:
The Hazen Williams equation can be written as follows:

where,
P = Friction Loss per foot of pipe =
= 4 x 10⁻⁴
Q = Flow Rate in gallon/min (gpm) = ?
d = pipe diameter in inches = (400 mm)(0.0393701 in/1 mm) = 15.75 in
C = roughness coefficient = 100
Therefore,

<u>Q = 913.9 gpm</u>
That is very true, but what is the question asking you.
Part (a): Magnetic dipole moment
Magnetic dipole moment = IA, I = Current, A = Area of the loop
Then,
Magnetic dipole moment = 2.6*π*0.15^2 = 0.184 Am^2
Part (b): Torque acting on the loop
T = IAB SinФ, where B = Magnetic field, Ф = Angle
Then,
T = Magnetic dipole moment*B*SinФ = 0.184*12*Sin 41 = 1.447 Nm
Yes that is correct or in other form, True
I would think that you would have to do 42/2=21Hz, but I'm not sure...