Question 1:
Orifice meters are used to measure the flow rate of a fluid. In an experiment, the flow coefficient K of an orifice is found by collecting and weighing water flowing through the orifice during a certain interval while the orifice is under a constant head. K is calculated from the following formula:
K = M / tAp(2gΔh)1/2
The values of the parameters have been determined to be as follows, with 95% confidence:
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Mass
Time
Density
Diameter
Head
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M = 393.00 ± 0.03 kg
t = 600.0 ± 1 s
p = 1000.0 ± 0.1% kg/m3
d = 1.270 ± 0.0025 cm (A is area)
Δh= 366.0 ± 0.3 cm
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Find the value of K, its uncertainty (with 95% confidence), and the maximum possible error.
Question 2:
A mechanical speed control system works on the basis of centrifugal force. Which is related to anugular velocity through the formula
F = mrω2
where F is the force, m is the mass of the rotating weights, r is the radius of rotation, is the angular velocity of the system. The following values are measured to determine ω:r = 20 ± 0.02 mm, m = 100 ± 0.5 g, and F = 500 ± 0.1 % N. Find the rotarional speed in rpm and its uncertainty. All measured values have a confidence level of 95%.