Problem: Derive the time period of a simple pendulum using dimensional analysis.
T depends on: length L, mass m, acceleration due to gravity g.
Let T = k * L^a * m^b * g^c
Dimensions: [T] = [L]^a * [M]^b * [LT^{-2}]^c
For M: 0 = b => b = 0 (T is independent of mass!) For L: 0 = a + c For T: 1 = -2c => c = -1/2 => a = 1/2
Therefore: T = k * sqrt(L/g)
The constant k = 2pi (cannot be found by dimensional analysis). Final: T = 2pi*sqrt(L/g)