All linear dimensions of the ring will increase by the same percentage.
delta L = L * alpha * delta T
where
delta L = change in linear dimension,
L = original value of linear dimension (at the reference temperature),
alpha = coefficient of thermal expansion,
dalta T = change of temperature...
If the pivot is fixed, it is effectively infinitely stiff.
Then the rotational natural frequency about 2 is:
f = sqrt[(k1.L12^2 + k3.L23^2)/(m1.L12^2 +m3.L23^2)] /2/pi
where
L12 = distance from 1 to 2
L23 = distance from 2 to 3
m1 = mass at 1
m3 = mass at 3
f = frequency
masses in kg...
The formula is wrong (by a factor of 100)
For a hydraulic, positive displacement motor or pump, torque is the same as work per radian and there are 2.pi radians in a revolution. Thus 2.pi.T = work done per rev, in joules per rev if T is in Nm.
Work done by fluid/rev = P.v where
P = pressure...
If you want to build up a sphere with equilateral triangles you can only use the tetrahedron. All the other regular solids use different face geometries. Clearly a 600mm sided triangle is not going to give a tetrahedron inscribed on a sphere of 11000mm diameter.
If approximations are allowed...