Question 1. the main goal of science is to
1)collect facts and learn “the truth”
2)understand nature
3)do wild and crazy experiments
4)is to produce facts
question 2. an observation is received directly or indirectly by
1)hearing
2)seeing
3)tasting/touch
4)all of the above
question 3. scientific fact can never change
1)true
2)false
question 4. a scientific theory
1)holds the highest level of acceptance
2)explains a number of facts
3)explains a number of facts
4)all of the above
5)none of the above
question 5. a scientific hypothesis starts with the lowest level of acceptance but can become stronger as they are used and survive repeated testing.
1)true
2)false
and ty < 3

An internally reversible refrigerator has a modified coefficient of performance accounting for realistic heat transfer processes of where qin is the refrigerator cooling rate, qout is the heat rejection rate, and is the power input. show that copm can be expressed in terms of the reservoir temperatures tc and th, the cold and hot thermal resistances rt, c and rt, h, and qin, as where rtot rt, c rt, h. also, show that the power input may be expressed as 1.39 a household refrigerator operates with cold- and hot-temperature reservoirs of tc 5 c and th 25 c, respectively. when new, the cold and hot side resistances are rc, n 0.05 k/w and rh, n 0.04 k/w, respectively. over time, dust accumulates on the refrigerator’s condenser coil, which is located behind the refrigerator, increasing the hot side resistance to rh, d 0.1 k/w. it is desired to have a refrigerator cooling rate of qin 750 w. using the results of problem 1.38, determine the modified coefficient of performance and the required power input w under (a) clean and (b) dusty coil conditions. internally reversible refrigerator qout qin w high-temperature reservoir low-temperature reservoir th th, i tc, i tc high-temperature side resistance low-temperature side resistance w qin th tc qinrtot tc qinrtot copm tc qinrtot th tc

What is the primary force that suspension bridges use cables to hold their spans up? a. tension force b. resistance force c. normal force d. elastic force e. applied force

Which of these is not a possible type of energy transformation? a. electrical energy into light energy b. sound energy into nuclear energy c. potential energy into kinetic energy d. kinetic energy into mechanical energy