#### MolaKule

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This exercise is a bit more involved and requires a Scientific Calculator and is open to all.
One way of measuring viscosity is to use a "Rotating Concentric Cylinder" viscosimeter, sometimes called a, "Couette" viscosimeter.
A rotating cylinder (the Inner Cylinder), is placed inside another (outer) cylinder and the fluid whose viscosity is to be measured in poured into the gap, g.
The Inner Cylinder is rotated at a specific RPM and the amount of Torque to rotate the Inner Cylinder is measured.
Note: * is multiplication and X^n is a number raised to the "nth" power since we don't have an equation editor in BITOG.
The viscosity is given by: u = T*g/(4*pi^2*R^3*n*L) = Absolute Viscosity in SI units of N.s/m^2
T is torque, measured at 1.8 N.m,
g is gap between Inner and Outer Cylinder, or 0.15 cm,
Outer Diameter of Inner Cylinder is 12 cm,
L is length of each each cylinder which is 40 cm long,
n is RPM, 300 RPM
R is Radius of Inner Cylinder.
Hints: Use 39.48 for 4*pi^2; Convert all given units to meters and seconds; answer will be in N.s/m^2.
We will disregard any "end" effects.
The result will be a 30 Grade motor oil at ~ 40C.

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