Question

Principle of continuity is based on conservation of:
1. energy
2. mass
3. both 1 and 2
4. None of the above

Answer 1

Correct Answer - Option 2 : mass

CONCEPT:

• Principle of Continuity: It shows the conservation of mass in a given space occupied by a fluid.
  • It says that the mass discharge for steady flow in a pipe is always constant; that is, 

ρVA = constant

where A is the cross-sectional area of the pipe and V is the mean velocity.

\(\rho_1V_1A_1=\rho_2V_2A_2\)

If the fluid is incompressible i.e. density is not changing when passing from one place to another place.

\(\rho V_1A_1=\rho V_2A_2\)

\(A_1V_1=A_2V_2\)

EXPLANATION:

According to the principle of continuity,

ρVA = constant

\(\rho_1V_1A_1=\rho_2V_2A_2\)

So, Mass passing from one cross-section area will be the same for another cross-section area.

So here mass is conserved.

Hence the correct answer is option 2.