You have been asked to identify the polymers used in two drinking cups. Both cups are clear. Suggest two identification tests (either physical or chemical) that will distinguish the cups, the probable results, and your rationale. The choices of plastics for the cups are polyethylene and polystyrene
What will be an ideal response?
A burn test will show polystyrene gives off a thick black smoke because of the benzene group. A flexural test will show PS being much more brittle than the PE and the PS will fracture long before the PE. PS will also be much more susceptible to chemicals. Some possible chemicals for the resistance test could be gasoline or acetone. PE will not be susceptible to either.
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Bore: 13.00 cm Stroke: 15.00 cm Clearance Volume: 131.1 cm^3 A) 16.4:1 B) 16.6:1 C) 16.8:1 D) 16.2:1
Two technicians are discussing how torque is increased inside a manual transmission/transaxle. Technician A says that the gear ratio in first gear between the main shaft and the countershaft should be multiplied by the ratio of the corresponding countershaft gear and output shaft gear. Technician B says that the two ratios should be added together. Which technician is correct?
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The outcome of a cooling and heating load is measured in ____________.
A. load calculation B. calculations C. manual J D. BTU
Why would 400 SPFM be better that 100 SFPM when carbide cutting tools?
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