Difference Between Ht Group And Group

The first variable tested was phototaxis, the movement toward or away from light. To do this, we used an empty petri dish and filled the bottom of it with filter paper. We then added five sowbugs to the petri dish and placed a lid on top. After leaving the sowbugs alone for three minutes to get acclimated to their new environment, we placed a lamp directly over the petri dish. Then we laid a piece of cardboard over the petri dish to cover exactly half of it, leaving the other half exposed to the lamp. We want the cardboard to cover close to half of it as possible to make the data as accurate as possible. The lamp was then turned on and the number of sowbugs in the light and dark locations were recorded every minute for the next twelve minutes. As shown in Table 1, we determined that sowbugs are effected negatively by phototaxis.

Boynton, R.M. 1987. Color. In McGraw-Hill Encyclopedia of Science & Technology (Vol. 4, 165-166) McGraw-Hill, Inc.

An investigation to measure the percentage light transmission, using a colorimeter, through a solution, from pH 2 – pH 9, in which jelly cubes were immersed over a 24 hour period

10 °C (50 °F) 0.006 0.006 0.007 0.006 20 °C (68 °F) 0.251 0.285 0.273 0.27 30 °C (86 °F) 0.767 0.789 0.799 0.785 Optical Density 40 °C 50 °C (104 °F) (122 °F) 0.969 0.93 0.947 0.922 0.945 0.947 0.954 0.933 60 °C (140 °F) 0.843 0.827 0.829 0.833 70 °C (158 °F) 0.641 0.623 0.632 0.632

The ending result of this experiment confirms that as five test tubes are lined up with the varying level of absorbance, different results in the level of absorbance will appear as well, this is visible in above table. Thus, this is due to the varying amount of water in the solution. The blank sample had a 0.30 in its level of absorbance.

The Beers Law calibration experiment used many concentrations of crystal violet solutions. Each of these solutions were test and analyzed in order to determine the absorbance of each concentration The results were than graphed and produced a slope of 1.00E05 with an intercept of -2.21E-02.

b. Describe the spectral curve of each target type with respect to its absorption and reflectance characteristics. (3)

After adding the anise oil, the mixture was allowed to heat for 20 minutes rather than 15 minutes as stated. Lastly, the IR spectrum analysis was previously prepared so no actual IR spectrum analysis was carried out during the course of the experiment.

The initial experiment was a success. As our treatment group spent more and more time under the lights, the absorbance rate continues to decrease toward zero. Once our 30 minutes were up, the absorbance rate in each tube was significantly lower than at the start of our experiment. In contrast the two control groups did significantly lower the absorbance. Each control lacked one of the vital aspects of photosynthesis, one being light, and the other being chloroplast. Neither of the control groups (Control 1 or 2) showed any signs of photosynthesis. Control 1 was exposed to light, but contained no photosynthetic organelles thus the absorbance throughout the 30 minutes varied minimally, mostly staying stagnant. Control two which contained chloroplast but was not exposed to any light failed to lower the absorbance at all and in fact increased the absorbance over the 30 minutes. However, the treatment group contained both and ultimately performed photosynthesis as we expect therefore, confirming our assumption that chloroplast were the organelles required for photosynthesis in plants and that light is required to perform said photosynthesis. The treatment group, containing both the chloroplast and being exposed to light provided evidence that photosynthesis was taking place as the absorbance lowered at each 10-minute interval. Having a less absorbance would be desired because as DCIP became reduced we would expect the solution to become more and more clear, thus less

In the study of the spectral range of 400-200 nm devices are used built on the same optical scheme as those for studying the visible range of the spectrum, the difference is only in the glass prisms, lenses, and other optical components. When measuring the intensity of UV emission, as a reference is used source in the UV region of the spectrum with known distribution of the spectral brightness (band tungsten lamp, coal arc, and synchrotron radiation). A thermocouple and graded solar cells are standard receivers in this region of the spectrum. Continue reading →

complex. The results were combined with findings from 4A and 4B to determine the empirical formula

The indices of refraction of water and plastic were 1.27 and 1.45 respectively, which were lower than the actual values of 1.33 and 1.46. The imprecision and the width of the light ray had decreased our calculated indices. Double refraction further decreased the index of refraction of water while the small plastic block was unable to cover the all the markings on the graph paper, causing difficulties in reading and a greater percentage error in the index of refraction of water. To increase the accuracy, we could use a graph paper with more markings since , and use a slit plate that has a smaller gap so that the light ray would be narrower and allow our measurements to be more precise. For the index of refraction of water, we could also measure

Human views of difference as solely a separating factor in our humanity simplifies our understanding of each other as complex beings with complex identities. Focusing on human differences rather than similarities has lead to the simplification of a human identity to a single, superficial trait, dividing humanity rather than unifying it. Claudia Rankine identifies and exemplifies this problem in Citizen, emphasizing the small incidents that show the harmful effects of this simplification. James Baldwin also defines the problems of this simplistic way of thinking and expands on Rankine’s claims to include a possible solution to this problem. People should not see others as simply black, simply women, simply gay. It is when people being to

We have timed each of the three experiments for 5 minutes to make sure that our results are correct. Thanks to the program, we got the transmittance and the absorbance, together with the graph portraying our results.

Table 2: Results of surface roughness obtained from optical profiler and results of % reflectance