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Chapter 2
est percent uncertainty in computing estimates of the weight of the contents
of the tanks.
PROBLEM 2.4
Flow in a circular pipe (laminar flow) is given
nd4~ht~
Q- 128~tL
What is the percentage uncertainty in the flow rate if:
Ca = 1%
P = 0.99
C~ = 3%
ChL = 2%
P = 0.99
C u = 3%
Ca = 3%
P = 0.99
P = 0.99
P = 0.99
Which uncertainty contributes most to the uncertainty in Q and find CQ.
PROBLEM 2.5
The following data represent the pumping ability of a certain type of pump.
(i.e. ten pumps of the same kind.)
OUTPUT(gal/min)
101 103 90 97 98 100 100 102 99 110
Pump#
1
2 3 4 5
6
7
8 9 10
The following table represents the pumping requirements for a country
estate:
DAY
Mon
Tues
Wed
Thurs
Fri
Sat
Sun
req.gpm
100
70
70
90
80
90
60
Assume that the above data are samples from Gaussian distributions.
When using a pump of the type given above, what is the probability of
failure? (i.e. not enough capacity.)
What is the factor of safety of the pump-country estate combination?
PROBLEM 2.6
An equilateral triangle, height b = 25.62" :k 0.010", is hung from long wires
and used as a torsional pendulum oscillating about a vertical axis. The test
sample center of gravity is above that of the plate and the test sample
moment of inertia is determined about a vertical line. The Ir from Weights