Hydraulics and Fluid Mechanics in ME
For similarity, in addition to models being geometrically similar to prototype, the following in both cases should also be equal

ratio of inertial force to force due to viscosity
ratio of inertial force to force due to gravitation
all the four ratios of inertial force to force due to viscosity, gravitation, surface tension, and elasticity
ratio of inertial force to force due to surface tension

ANSWER DOWNLOAD EXAMIANS APP

Hydraulics and Fluid Mechanics in ME
Coefficient of resistance is the ratio of

Actual velocity of jet at vena-contracta to the theoretical velocity
Actual discharge through an orifice to the theoretical discharge
Loss of head in the orifice to the head of water available at the exit of the orifice
Area of jet at vena-contracta to the area of orifice

ANSWER DOWNLOAD EXAMIANS APP