A pair of Helmholtz coils has a total of
500 turns and is carrying a current of 2.5 A. The radius is 7.5 cm
and the two coils are 7.5 cm apart. Calculate the magnetic flux
density.

Formula:

B =(0.8)^{1.5}
× (4p × 10^{-7} H m^{-1} × 500 × 2.5) ÷ 7.5 × 10^{-2}
m