1. A creep test was performed on a wire where the increase in percent strain (e) over

time (t) as a constant load is applied is measured as follows:

time (min): 1.587 3.088 4.590 6.091 7.592 9.094

% strain: 0.08 0.15 0.20 0.29 0.35 0.42

Determine the linear relation between percent strain and time. What will be the

percent strain: at 12 minutes? [note: e = k t]

2. A source of gamma rays was employed to give measured doses of radiation in an

experiment. However, the dosage varied with position in the apparatus as shown

by the data:

position from base point, x (inch): 0. 0.5 1.0 1.5 2.0 3.0 3.5 4.0

dosage, d (105 rads/hr): 1.90 2.39 2.71 2.98 3.92 4.20 4.56 4.88

Generate the linear equation and calculate the missing dosage level at x = 2.5

Inch

3. By measuring the water flow depth (h) over a rectangular weir of width (B) the

volume flow rates (Q) in a channel can be calculated using the following weir

equation:

Q (ft3/s) = [ Cd ( 2 g ) B ] hn (B, h in ft units)

Determine the values of Cd and n based on the following laboratory test data for a

weir of width 6 inches (g = 32.2 ft/sec2).

[note: ln(Q) = ln[ Cd ( 2 g ) B] + n ln(h)

Q (ft3/min): 161 123 87 56 30 11

h (inch): 12 10 8 6 4 2

4. Andrade’s equation relating viscosity, μ (N.s/m2) with temperature, T (K) for liquids

is given by

(B 1/T ) μ = De

Develop Andrade’s equation for water using the following data:

[note: ln ( μ) = ln (D) + B (1/T) ]

temperature, T (oC): 0 20 40 60 80 100

viscosity, μ (N.s/m2x10-3): 1.787 1.002 0.6529 0.4665 0.3547 0.2818

Estimate the viscosity of water at 30 oC and calculate the percent true error