The specific energy (energy per unit mass) of a space vehicle is composed of two components, the specific potential energy and the specific kinetic energy.

The formula for specific kinetic energyis given as,

ϵ_k = ½ ×velocity

ϵ_k = v² / 2

ϵ_k = specific kinetic energy

v = velocity

The specific energy (energy per unit mass) of a space vehicle is composed of two components, the specific potential energy and the specific kinetic energy.

The formula for specific potential energy associated with a planet of mass M is given by

ϵ_p = − universal gravitational constant ×Mass / distance

ϵ_p = − GM / r

 ϵ_p = specific potential energy

G = the universal gravitational constant (G = 6.67×10−11 m3 kg−1 s−2),

M = the mass of the body to be escaped

r = distance from the centre of mass of the body to the object.

Coefficient of viscosity of a liquid is defined as the viscous force acting per unit area between two adjacent layers of a liquid with a velocity gradient normal to the direction of flow of the liquid.

The formula for Coefficient of viscosity (η) of a liquid is given as,

where F= viscous force , A = Area , (dv/dx) = velocity gradient

η = F / A(dv/dx) .

SI unit of Coefficient of viscosity (η) of liquid is kg m^-1 s^-1.

Velocity Gradient is defined as the ratio of increase of velocity to the distance across which the increase occurs.

The formula for velocity gradient is given as,

Velocity Gradient = velocity/distance.

In fluid mechanics ,

Velocity Gradient is defined as the variation in velocity among the adjacent layers of the fluid. The difference in the flow of velocity between the  adjacent layers of the fluid is measured in velocity gradient.

The formula for velocity gradient is given as,

Velocity Gradient = Difference in flow velocity between the layers / distance between the layers.

SI unit of Velocity Gradient is s^-1.

Hydrostatic Pressure is the thrust (normal force) applied by a liquid at rest per unit area to the surface in contact with a liquid. Hydrostatic Pressure is also known as Pressure of liquid.

The formula for pressure is given as,

Pressure  =  Force /Area 

The pressure (P) exerted by liquids depends on Height (h) of the liquid column ,Density of liquid (ρ) and Acceleration due to gravity (g).

The formula for pressure of liquid can also be expressed as,

Pressure of liquid ( Hydrostatic Pressure) =  h ρ g.

Pressure is a scalar Quantity and SI unit of Hydrostatic Pressure is N / m² or Pascal (Pa)