def froude_number(speed, length):
g = <NUM_LIT>  <EOL>Fr = speed / np.sqrt(g * length)<EOL>return Fr<EOL>
Froude number utility function that return Froude number for vehicle at specific length and speed.

:param speed: m/s speed of the vehicle
:param length: metres length of the vehicle
:return: Froude number of the vehicle (dimensionless)