Retort stand and clamp Essay Example

Retort stand and clamp Essay Example Retort stand and clamp Paper Retort stand and clamp Paper In reference to the safety aspect, the radiation source is kept inside a lead block, inside a wooden box, inside another wooden block, tongues are present for the movement of the source so it never directly handled. The sources themselves are in holders, which channel the radioactive output in one direction alone. However as I am working with Gamma radiation this is slightly irrelevant. Also the rad-count dector will be placed in a clamp, to ensure its constant position. The radiation source itself is placed in a L-frame; this will keep it at a constant height. It also reduces the amount of handling needed of the sample. I also made sure that I was over 16 years of age before beginning, and made a concerted effort not to ingest the radiation source. Method 1. ) Take the background count of radiation by turning on the digital radcount, and setting to detection for 1 minute three times. 2. ) Remove the cobalt-60 from its lead container, and using tweezers put in the l-frame source rig. 3. ) Securely attach a metre rule to the desk, brace the l-frame against it, with the vertical section corresponding to a whole number on the metre rule 4. ) Secure the digital rad-count dector in a clamp attached to a retort stand, align this with the cobalt-60 and place it to be touching. 5. ) Set the digital rad-count to detection, for one minute, do this three times 6. ) Move the l-frame what you estimate to be 2. 5 mm from the digital rad-count, and set the digital vernier callipers to 2. 5 mm, cheek the distance of the l-frame and refine as necessary. 7. ) Repeat steps five and six until a distance of 3cm is achieved. Repeat step 1 at distance 1. 5 cm and 3cm. Analysis of Results I feel that my results prove that gamma radiation does obey the inverse square law; to begin with we will look at the graph in which the radiation count is plotted against distance A curve is described thus suggesting that intensity is inversely proportional to the distance. However this graph goes no way to prove that it is inversely proportional to the square of the distance, for that we need to construct a graph with one over the square root of the radiation count plotted against distance. My graph clearly shows a straight line. Thus it is shown that Gamma radiation obeys the inverse square law. However the Equation I achieve is actually Y= -0. 77X + 3. 02, but rather than proving that gamma radiation doesnt obey the inverse square law, I feel it merely points out certain experimental errors, namely the inaccuracies in distance. Although they may only have been +- 0. 5 mm, when working on a scale of 2. 5 mm at times the percentage error is very high. So I feel that these graphs more than adequately prove the inverse square law holds for gamma radiation. My trial experiment in light also proves that the inverse square law holds for light. In a similar method to the gamma experiment if we plot a graph of light intensity against distance, we obtain a curve. The fact it is a curve is good, however it is more than that it is a curve, with an almost perfect half life, the value not changing significantly for each half-life. Being around 2. 5cm. The fact it has such a good half-life makes the need for further graphs redundant, it conclusively proves the inverse square law. The half-life shows that if the distance is doubled the intensity is decreased by a factor of four. The fact that light and gamma radiation obey the inverse square law is solid proof that all members of the electromagnetic spectrum will obey the inverse square law. Evaluation Systematic Errors There was a high uncertainty in my measurement of distance. The cobalt 60 is kept within a metal tube. During my experimental procedure, I measured from the front of this tube, however the source could have been up to 5mm into the tube. Over short distances this leads to very high percentage errors. A similar thing is present in the Geiger-muller counter and tube. Like previously the actual dector is set inside the plastic casing, and could have been up to 5mm inside the tube. This leads to very high percentage errors again, which I will calculate later. There is a possibility that the counter and radiation source were actually slightly out of line, so as the two moved apart, there would be a horizontal angular discrepancy, this would lead to a count lower than it should be. However, attaching a meter rule to the desktop and bracing both the source clamp and the retort stand against it, and ensuring the two align as closely as possible, this problem is solved, this should also solve the problem on the vertical angular discrepancy. More extreme measures include bracing the equipment against the secure ruler to eliminate horizontal angular discrepancies, and attaching mini spirit levels to the source and detector to ensure the vertical angular discrepancies are kept to a minimum. It could also be possible to attach a laser pen to one of the pieces of equipment and ensuring the position of the laser light on the opposing piece of equipment doesnt change. This will eliminate both horizontal and vertical angular discrepancies. However these tow suggestions are impractical, the only laser light I have access to is actually very powerful, and could easily blind if directed at the ye, so I feel the danger levels here are to high. I only have access to large sprit levels, which would not be practical to attach to the equipment. Plus as I am only working over small distances any angular discrepancy will not produce high percentage errors. Another possible error would be if the count exceeds the level at which the dector could perceive. This would lead to what is known as dead time. As there is radioactive activity not being detected hence a deceptively low count would be present. But for this to occur it would require radiation counts far in excess of what the weak Gamma source I used was capable of, so this can be ignored.

ACT Scores

Who Uses SAT/ACT Scores SAT / ACT Prep Online Guides and Tips Your SAT/ACT score isn't a one-trick pony. Wondering why your SAT/ACT scores are important? They’re used for more than just college admissions. Get a list here of who uses SAT/ACT scores, and why. You may be surprised how late into life your SAT/ACT scores can follow you! College Admissions Not surprisingly, your SAT/ACT score is a very big part of the admissions process. In fact, hour for hour, studying for either the SAT/ACT could be the most efficient way to improve your college admissions chances. But why? SAT/ACT scores are so important because while GPA and class difficulty varies from school to school, every student takes either the SAT or ACT. It’s easier for college admissions officers to compare students from different cities or states by using the ACT/SAT, rather than their GPA. After all, a 4.0 could mean very different things at different schools, but a 36 on the ACT looks impressive no matter what. Of course, many colleges use holistic admission processes, meaning they also consider your GPA, class schedule, extracurricular activities, essays, and more when making your admission decision. But out of all of these factors, the SAT/ACT is one of the most, if not the most, important one. This is why the vast majority of colleges require an SAT/ACT score to apply. There are exceptions: schools that have no standardized tests required or flexible standardized testing. Some well-known ones include NYU, Bryn Mawr and many of the other seven sisters colleges, and George Washington University. But for now these are the exception and not the rule! So definitely plan on studying hard for either the SAT or the ACT for the best shot at your dream school. Freshman Year Course Placement Furthermore, some schools use the SAT/ACT for first-year course placement. So beyond just helping you get admitted to college, your SAT/ACT score could affect your first-year class schedule! To take an example, let’s look at the University of Nevada. They use SAT/ACT scores to place students in their first chemistry, math, and English classes. To look at just one subject, for the freshmen English class, placement is as follows, based on Writing section scores: Eng 098: ACT 17/ SAT 430 or below English 100I: ACT 18-20 / SAT 440-500 English 101: ACT 21-29/ SAT 510-670 English 102: ACT 30 + / SAT 680 + So even if you have a high enough score to get into a college, the higher your score, the higher your class placement could be. If you’re curious about a school you want to apply to, and whether or not it uses the ACT/SAT for class placement, look up â€Å"[Name of College/University] First Year Course Placement.† Some colleges have their own placement tests, and still others use AP/IB scores instead. Scholarships Your SAT/ACT score is often an important criterion for scholarship selection. So not only can your ACT/SAT score get you into college, it could help you pay for it! We’ll break this discussion down into private and school-run merit scholarships. Private Scholarships Private scholarships are scholarships funded by organizations, companies, or individuals. Many private scholarships, especially large ones, require an application from interested students. Just like for college admissions, the SAT/ACT is a standard barometer of success for all students – which is why private scholarships often include SAT/ACT score on their applications. Requiring the SAT/ACT on applications allows private scholarships to compare students from different schools. Generally, the higher your SAT/ACT score, the higher your odds of winning the scholarship. This $50,000 max scholarship, for one, requires SAT/ACT scores for the application.The National Merit Scholarship is another scholarship that depends on your SAT score specifically (not the ACT), as well as getting a qualifying PSAT score. (Read more about National Merit here.) Merit Scholarships Many colleges and universities – especially larger state schools – often give scholarships based on merit. These scholarships reward the most accomplished students entering the school, and are used to help convince high-achieving students to attend. These scholarships are often highly dependent on your GPA and SAT/ACT score. In fact, there are often different award amounts that increase along with your SAT/ACT score. See our list of automatic scholarships for SAT/ACT scores to find out more! Talent Searches Some students may find themselves taking the SAT/ACT quite early on. Middle school talent searches (like Duke TIP or Johns Hopkins CTY) require the SAT/ACT as part of the process. These talent searches give gifted students access to special courses, college counseling, and more. Your scores are judged differently for these since you’re taking the SAT/ACT at a younger age. (You can read about the SAT and ACT score requirements for Duke TIP if you're curious.) And in case you’re wondering, colleges don’t need to see scores from very early SAT/ACT dates when you’re applying. If you take the SAT/ACT in middle school, you should probably retake it in high school for a higher score. Job Applications Even once you’ve graduated college, your SAT/ACT score can follow you! Even though both tests were designed for college admissions, some other organizations have found uses for them. In particular, sometimes SAT/ACT scores are used for job applications (particularly at prestigious companies like Bain, McKinsey, and Goldman Sachs) to see if applicants have the â€Å"raw brainpower needed† to succeed. Does this make sense? Maybe not. According to an article in Time, â€Å"SAT scores might not even be that good of a barometer for predicting someone’s job performance. In an interview last year, Google HR exec Laszlo Block told the New York Times, 'Google famously used to ask everyone for a transcript and G.P.A.’s and test scores, but we don’t anymore, unless you’re just a few years out of school. We found that they don’t predict anything.' When the search engine giant crunched the numbers, it couldn’t establish a link.† So why do companies sometimes include SAT/ACT score on their applications? According to a PBS Newshour Report, "'When you’re hiring people and they don’t have a lot of work experience, you have to start with some set of data points,' Eric Eden of Cvent, a Virginia-based software company, told The Wall Street Journal. Eden’s company hasn’t looked into whether their top employees also had the highest scores - but 'knowing it’s a standardized test is really enough for us,' he said.' So even though it might not make the most sense, some companies will look at your high school SAT/ACT scores to get more context about you. Since the SAT and ACT are standardized, the tests allow the companies to easily compare different applicants. Will your SAT/ACT scores stop you from pursuing your dream career? No. The majority of companies don't ask for your SAT/ACT score on your application. But some do, so your SAT/ACT scores could affect your job prospects, especially right out of college. This is just another reason to study hard in high school! How the SAT/ACT Won’t Be Used After reading all this, you may be thinking your ACT/SAT scores will follow you around for the rest of your life. But don't worry! There are some key opportunities, both pre- and post-college, that don't use your SAT/ACT score. Graduate fellowships like the Rhodes, Marshall, and Fulbright scholarships don’t require SAT/ACT scores – for these, your undergraduate transcript is most important. So if you have your eye on getting one of these prestigious scholarships, don’t worry about your SAT/ACT score following you. Graduate Schools don’t take the SAT/ACT either. In fact, each type of grad school has its own test. Prospective medical students have to take the MCAT, law students the LSAT, pharmacy students the PCAT, dental students the DAT, business students the GMAT or GRE, and many other programs require the GRE. (Talk about alphabet soup!) So even if you ace the ACT/SAT in high school, you’ll have to go through the test prep routine once more if you're aiming for graduate school. Finally, some private scholarships (like the Coca Cola scholarship) don’t use SAT/ACT scores. In fact, there are many private scholarships based just on essay competitions or other writing prompts. Many more are also based on your personal circumstances, for example, scholarships for children of military members. You can search for scholarships on College Board's Big Future website if you want to find out more. Bottom Line Your SAT/ACT score doesn’t just matter for college admissions – it can get you scholarships, higher class placements, and even a job post-college! This is all the more reason to study for these tests as hard as you can. That said, don't stress about the SAT/ACT too much. For most students, once they get to college, the tests will stop being important. Even if a job application asks for your SAT/ACT score, they will also be looking at your achievements and work experience from college. So focus on doing the best at whatever it is you're working on now! What’s Next? So you know your SAT/ACT scores matter. But what kind of scores do you need for your dream schools? Find out the SAT score or ACT score you need to be competitive. Should you retake the SAT/ACT? Find out here how likely it is your score will improve. Get more in-depth advice for improving your SAT/ACT score, from the best ACT English practice, vocabulary you need for SAT reading, a guide to lines and angles on SAT math, and the 21 ACT tips you should be using. Want to improve your SAT score by 160 points or your ACT score by 4 points?We've written a guide for each test about the top 5 strategies you must be using to have a shot at improving your score. Download it for free now: