1. (not from the text) Damped Harmonic Motion: (2 points)
y= e cos(2neft)
Note: The cos(2neft part is simple harmonic motion. The e part is exponential decay.
The net result should be harmonic motion with amplitude that decreases with time.
k= 3 (units of /s or s')
f=4 Hz
Plot y vs. t
Add a title to the plot (e. g., "Position vs. Time").
Label the t and y axes. Include the units of seconds (s) on the time axis.
Note: Here, y is dimensionless. If y had some initial starting amplitude A, then that
would contain the units on y (e. g., meters m).
Tip: For a starting point, try t=0 to 5s, in 0.01s increments.

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A3-mm-thick panel of aluminum alloy (k 177 w/m-k, c 875 j/kg-k and ? = 2770 kg/m) is finished on both sides with an epoxy coating that must be cured at or above t,-150°c for at least 5 min. the production line for the curing operation involves two steps: (1) heating in a large oven with air at ts,0-175°c and a convection coefficient of h, 40 w/m2. k, and (2) cooling in a large chamber with air at 25°c and a con- vection coefficient of he 10 w/m2.k. the heating portion of the process is conducted over a time interval te which exceeds the ime required to reach 150°c by 5 min (h = r + 300 s). the coating has an emissivity of ? = 0.8, and the temperatures of the oven and chamber walls are 175 and 25°c, respectively. if the panel is placed in the oven at an initial temperature of 25°c and removed from the chamber at a safe-to-touch tempera ture of 37°c, what is the total elapsed time for the two-step curing operation?