Also, we lacked precision in timing, and should've used a more precise stopwatch to make sure it was a fair test. We also didn't have the same intervals for the measuring of time, which would've not made our experiment
It was also because we had to take two measurements (one for diameter another for height)...which could possibly create more mistakes. Furthermore, you need to multiply diameter and height to get to the volume, so any one of those reading had a mistake, the error would compound and get worse. The same is not true with measuring with graduated cylinder, which is just a one shot reading. If that reading is off a bit, it won't impact the density as much 2- Did you find that density was intensive or extensive? Explain A- It was intensive.
A null hypothesis is the hypothesis that there is no significant difference between specific populations, where observed differences are due to errors. The Hardy-Weinberg Theory is a null hypothesis and that is what we tested in this experiment. The only time a null hypothesis can be accepted or rejected but cannot be proven. It may be quantified as true, but it cannot be proven. The reason for this is because in tests like these observed differences are usually due to chance differences in sampling.
The results were that the chance of developing a cold correlated with stress index scores. The life event lowered the immune function and increased vulnerability to the virus. However there were several problems with this research, one of which was that it was an indirect study- there was no direct measure of the immune system for example no blood test or medical test was taken as evidence. Consequently we cannot determine how far the participant’s immune system was affected in relation to the stress. Another key problem was that there were was no direct manipulation of the independent variable so the study doesn’t tell us which element of the stress index is most important and related to the decrease in immune function.
These issues could affect the external validity of the results –the results could be valid within the study but (high internal validity) but outside the study they are not- this means the results are harder to generalise to the target population. In all studies carried out in to circadian rhythms participants were removed from all obvious extraneous variables that could affect the running time of their circadian rhythm however they were not removed from artificial light. This could cause problems for the results found because Czeisler found that he could manipulate the participant’s circadian rhythms down to 22 hours and up to 28 hours using dim artificial light alone. This ability to manipulate the participant’s rhythms means the studies would then lack internal validity because even within the study results are not valid. On the other hand of the pervious evaluation point, not allowing participant’s to have artificial light during the experiments means that they are trapped in a dark cave or place for as long as six months.
2. The procedural error might have been due to the student not setting up the distillation apparatus correctly in par with the thermometer. The position of the thermometer might have caused that error as well. The top of the thermometer bulb might have been above the bottom of the side arm on the distilling head. 3.
Various approaches could have been used to compensate for the lack of personal privacy and informed consent but were not. Due to the sensitive nature of this study and the violation of many commonly accepted guidelines for research, this experiment shows to be unethical.
It was found however that the method of utilizing a calibration curve proved fruitless in determining fluorine ion concentration, as the calculated value of fluoride ion’s in drinking water was 13.29ppm, where the required value by law must fall within the range of 0.9-1.5ppm. Since this calculated value is so ridiculous, the method of standard addition, in which the calculated value of the unknown solution being measured was much higher than the calibration curve (4.81E-3M verses 3.78E-4M), should be a preferred method for calculated low concentration ion solutions compared to that of a linear calibration curve. Introduction: Fluoride is a necessary component in minimizing tooth decay by helping rebuild enamel. Because of this chemicals very effective ability to complete this task, the fluoride ion can be found in toothpaste. The associated salt (NaF) is often put into substances that are utilized every day, such as tap water and certain food products, in order to help prevent dental problems of the general population.
Maybe back in the not yet so advanced technological days, dummies were not equipped with contact points that register the point of contact and the amount of pressure of force exerted when contact was made with the dummy and at what speed the body of the dummy traveled past the point of the abrupt stop. That being said, the use of cadavers would give that information after the crash test during the autopsy without all of that technology being available to the testing facilitators. Even though cadavers were the “better choice,” as far as results go, I don’t think that using cadavers is a moral or good ethical choice. However, how is this different from cadavers being used for medical students to practice autopsies and mock surgeries? People might say because of the violent nature of the crash test vs. “just” being cut on.
Which, in turn, means the pipes were made from polypropylene. During the experiment it is possible that mass of each object was calculated incorrectly. To prevent such discrepancies, I can be sure to zero the scale. Although minute, temperature can affect the densities of various objects. Usually, when the temperature of objects is decreased the densities are increased and vice versa.