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FLUID MECHANICS
Example 4.3
The weight of an empty bucket is 2.0 kg. After 7 seconds of collecting water the weight of
the bucket is 8.0 kg. Calculate the mass flowrate of the fluid.
Solution to Example 4.3
• mass flowrate in bucket
mass flowrate, m =
time taken to collect the fluid
0 . 8 − 0 . 2
=
7
= . 0 857 kg s /
4.3 CONTINUITY EQUATION LAW
For continuity of flow in any system of fluid flow, the total amount of fluid entering the
system must equal the amount leaving the system. This occurs in the case of uniform flow
and steady flow. (Figure 4.2)
P R
QP QR
SYSTEM
Figure 4.2 : Continuity Equation system
QP = discharge through cross-section P-P
AP = cross-sectional area through P-P
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