The pressure outside the vacuum cleaner is greater than thepressure inside it which is almost a vacuum. Therefore, thispressure difference causes the dirt to be pushed inside the vacuum cleaner.

Question

asked 2021-08-22

The seller of a loaded die claims that it will favor the outcome 6. We don't believe that claim, and roll the die 200 times to test an appropriate hypothesis. Our P-value turns out to be 0.03. Which conclusion is appropriate? Explain.

a) There's a 3% chance that the die is fair.

b) There's a 97% chance that the die is fair.

c) There 's a 3% chance that a loaded die could randomly produce the results we observed, so it's reasonable to conclude that the die is fair.

d) There's a 3% chance that a fair die could randomly produce the results we observed, so it's reasonable to conclude that the die is loaded.

a) There's a 3% chance that the die is fair.

b) There's a 97% chance that the die is fair.

c) There 's a 3% chance that a loaded die could randomly produce the results we observed, so it's reasonable to conclude that the die is fair.

d) There's a 3% chance that a fair die could randomly produce the results we observed, so it's reasonable to conclude that the die is loaded.

asked 2021-07-30

A paper reported a \(\displaystyle{\left({1}-\alpha\right)}\) confidence interval for the proportion of voters is (0.561,0.599) based on a sample of 2,056 people. However, the paper omitted the value of \(\displaystyle\alpha\). If you want to test the hypothesis that the proportion of voters is greater than \(\displaystyle{65}\%\) at \(\displaystyle{1}\%\) significance, find \(\displaystyle{z}_{{{c}{a}{l}{c}}}\) value for this problem? Please report your answer to 2 decimal places.

asked 2021-04-21

The best laboratory vacuum has a pressure of about \(\displaystyle{1.00}\cdot{10}^{{-{18}}}\) atm, or \(\displaystyle{1.01}\cdot{10}^{{-{13}}}{P}{a}\). How many gas molecules are there per cubic centimeter in such a vacuum at 293 K?

asked 2021-04-11

The equation F=−vex(dm/dt) for the thrust on a rocket, can also be applied to an airplane propeller. In fact, there are two contributions to the thrust: one positive and one negative. The positive contribution comes from air pushed backward, away from the propeller (so dm/dt<0), at a speed vex relative to the propeller. The negative contribution comes from this same quantity of air flowing into the front of the propeller (so dm/dt>0) at speed v, equal to the speed of the airplane through the air.

For a Cessna 182 (a single-engine airplane) flying at 130 km/h, 150 kg of air flows through the propeller each second and the propeller develops a net thrust of 1300 N. Determine the speed increase (in km/h) that the propeller imparts to the air.

For a Cessna 182 (a single-engine airplane) flying at 130 km/h, 150 kg of air flows through the propeller each second and the propeller develops a net thrust of 1300 N. Determine the speed increase (in km/h) that the propeller imparts to the air.