Experiment 1: A study is done to determine which of two fuel mixtures allows a rocket to travel farther over a period of time. R
ocket A, which requires additional equipment to keep it stable, is used to test one fuel mixture, and rocket B is used to test the other. Both rockets are identical aside from their mass. The results indicate that rocket B traveled farther than rocket A over the same period of time. Experiment 2: A double-blind experiment is performed to test whether a new drug is effective in lowering blood pressure. A random sample of subjects with high blood pressure is assigned to two groups. One group receives the new drug and the other group does not. Neither group is permitted to take any other medications during the experiment or to change their lifestyles in any way. The results of the experiment show that the drug is effective in lowering blood pressure. Identify the experiment in which confounding occurs and the reason for its occurrence.
a. Neither experiment has a confounding variable.
b. Experiment 1 has a confounding variable related to the fuel mixtures. Varying the fuel mixture could skew the results of the study and should be kept constant.
c. Experiment 2 has a confounding variable related to the type of experiment. A double-blind experiment may increase the risk of the placebo effect and possibly skew the results.
d. Experiment 1 has a confounding variable related to the mass of the rockets. Any variation in mass may cause a discrepancy in the distance traveled.
e. Experiment 2 has a confounding variable related to the subjects used. Choosing a sample of subjects with high blood pressure instead of individuals with different blood pressure levels may confuse the results.
A nerve signal travels 150 meters per second. It is the speed of the nerve signal. We need to convert the number of kilometers that the nerve signal will travel in the same time.
We know that,
1 kilometer = 1000 meter
1 hour = 3600 seconds
So, the nerve signal will travel at the rate of 540 km/h. Hence, this is the required solution.
a. The force acting down is gravity, on Earth gravity is 10 m/s^2. When the skydiver jump, the acceleration will start out as -10 m/s^2, but it will eventually equals the air resistance , which is called terminal velocity.