Question

In a laminar flow of a liquid down an inclined plane, the surface velocity is found to be 60 cm/s. the average velocity of the flow in cm/s is:
1. 40
2. 120
3. 15
4. 30

Answer 1

Correct Answer - Option 1 : 40

Explanation:

Concept:

\({V_{avg}} = \frac{{2\;}}{3} \times {V_{max}}\)

V_max is the maximum velocity or surface velocity.

Calculation:

Given:

Vmax = 60 cm/s.

\({V_{avg}} = \frac{{2\;}}{3} \times {V_{max}}\)

\({V_{avg}} = \frac{{2\;}}{3} \times {60{}}\)

Vavg= 40 cm/s.

Note:

Velocity profile In a laminar flow of a liquid down an inclined plane is parabolic in nature.