Question

the method for act science
2 bends in a pipe and variations in pipe diameter create pressure differentials that cause fluids to undergo mixing. according to the diagram, where would mixing of air and propane most likely occur to support combustion?
f. arms
g. t - junction
h. single pipe
j. tube

1. the researchers had predicted that the burn - box approach would best simulate the temperature profile of growing - season prescribed fires. are the results of the study consistent with this prediction?

a. yes; the maximum mean temperatures for both growing - season and burn - box fires was around 350°c.
b. yes; the maximum mean temperatures for both growing - season and burn - box fires was around 650°c.
c. no; the maximum mean temperature for growing - season fires was 650°c, whereas the maximum mean temperature for burn box was 350°c.
d. no; the maximum mean temperature for growing - season fires was 350°c, whereas the maximum mean temperature for burn box was 650°c.

1. experiment 2 differed from experiment 3 in which of the following ways?

a. in experiment 2, timothy hay was added to adjust the fuel load, whereas in experiment 3, greenhouse - grown plants were added to adjust the fuel load.
b. in experiment 2, natural habitat plants were burned, whereas in experiment 3, greenhouse - grown plants were burned.
c. a propane torch was used to ignite the fire in experiment 2, whereas a ring - fire technique was used to ignite the fire in experiment 3.
d. the average fuel load in experiment 2 was 5,036 kg ha⁻¹, whereas the average fuel load in experiment 3 was 3,000 kg ha⁻¹.

1. suppose the maximum mean temperature and heat duration of an additional trial were 300°c and 175 sec, respectively. the time - temperature profile for this trial would most likely have been for a:

f. dormant - season prescribed fire.
g. burn - box fire.
h. burn - table fire.
j. propane - prong fire.
this data is from fire ecology, vol. 11, iss. 3, december 2015, pp. 34 - 44.
figure 2
key
—— burn box

• - - burn table

······ propane prong

Explanation:

1. Answer: A

• Brief Explanation: We need to find the difference between Experiment 2 and Experiment 3. By referring to the details in the text (which are not fully shown here but based on the options), Option A correctly states that in Experiment 2, timothy - hay was added to adjust the fuel load, and in Experiment 3, greenhouse - grown plants were added to adjust the fuel load.

1. Answer: G

• Brief Explanation: Bends in a pipe and variations in pipe diameter create pressure differentials for fluid mixing. A T - junction is a place where such bends and diameter changes can occur, facilitating the mixing of air and propane for combustion.

1. Answer: C

• Brief Explanation: Looking at the temperature - heat duration graph, the maximum mean temperature for growing - season fires is around 650°C and for burn - box fires is around 350°C. Since these values don't match, the results are not consistent with the prediction.

1. Answer: G

• Brief Explanation: Comparing the maximum mean temperature of 300°C and heat duration of 175 sec with the values in the graph for different fire types, it most closely resembles the characteristics of a burn - box fire.

Answer:

1. Answer: A

• Brief Explanation: We need to find the difference between Experiment 2 and Experiment 3. By referring to the details in the text (which are not fully shown here but based on the options), Option A correctly states that in Experiment 2, timothy - hay was added to adjust the fuel load, and in Experiment 3, greenhouse - grown plants were added to adjust the fuel load.

1. Answer: G

• Brief Explanation: Bends in a pipe and variations in pipe diameter create pressure differentials for fluid mixing. A T - junction is a place where such bends and diameter changes can occur, facilitating the mixing of air and propane for combustion.

1. Answer: C

• Brief Explanation: Looking at the temperature - heat duration graph, the maximum mean temperature for growing - season fires is around 650°C and for burn - box fires is around 350°C. Since these values don't match, the results are not consistent with the prediction.

1. Answer: G

• Brief Explanation: Comparing the maximum mean temperature of 300°C and heat duration of 175 sec with the values in the graph for different fire types, it most closely resembles the characteristics of a burn - box fire.