Rutherford's Alpha Particle Scattering Experiment
Rutherford was the world leader in alpha-particle physics. In 1906, at
McGill, he had been the first to detect slight deflections of alphas
on passage through matter. In 1907, he became a professor at the
University of Manchester, where he worked with Hans Geiger. This was
just a year after Rutherford's old boss, J. J. Thomson, had written a
paper on his plum pudding atomic model suggesting that the number of
electrons in an atom was about the same as the atomic number. (Not
long before, people had speculated that atoms might contain thousands
of electrons. They were assuming that the electrons contributed a good
fraction of the atom's mass.)
Rutherford's alpha scattering experiments were the first experiments
in which individual particles were systematically scattered and
detected. This is now the standard operating procedure of particle
physics. Rutherford's partner in the initial phase of this work was
Hans Geiger, who later developed the Geiger counter to detect and
count fast particles.
The experiment was conducted, as is shown below. Alpha particles were
fired from a source (from within a lead "shield") at a sheet of thin
gold foil (which had been beaten to about 400 atoms thick. A
fluorescent screen was placed behind / around the gold foil. Every
time an Alpha particle hit the screen a flash of light, or
"scintillation" was produced. This was conducted inside a vacuum (To
minimize alpha loss by scattering from air molecules).
Most of the particles went straight through the foil without any
deflection - however some of the particles (about 1 in 8000) were
deflected by a degree of more than 90 degrees.
This meant that the idea of the "Plum pudding" model (suggested by
J.J. Thompson in 1906) was in dispute - a model which Rutherford
himself had been a believer in.
Rutherford pondered this problem for some months. He eventually
decided there was simply no way it could generate the strength of
electric field necessary to deflect the fast moving alphas.
All throughout life we encounter situations where an acute sense of attention and focus is essential to achieve a goal and overcome obstacles. One such instance was Walter Mischel’s Marshmallow Test, introduced in 1986. His experiment prompted young children into situations that strained their ability to use focus and attention to achieve a goal. In this case, the goal was to be able to wait 15 minutes to be able to eat two marshmallow, instead of just eating the single marshmallow in front of you. Mischel claimed that children who were able to display a “delay of gratification” showed vastly higher SAT scores later in life compared to the children who decided to eat the first marshmallow outright. However, Sarah Kliff brings up the argument
The "2nd U.S. Circuit Court of Appeals" held that those business practices that have had a disparate impact effect on the older workers are now considered to be actionable under one national anti-discrimination law (Hamblett, 2004). The case does reaffirm a second Circuit precedent that had been set but which is at odds with what a majority of federal courts have held. The appeals court supported the idea that a layoff plan had been properly brought under the The Age Discrimination in Employment Act of 1967 (ADEA) although the company did not have the intention of discriminating.
Alcoholism is as prevalent in my family, as blood is in our veins. When previously asked to observe 12-step groups, I ritualistically flocked to Alcoholics Anonymous, without consideration of the possibility that other groups had any potential to make an impact on me. I always pride myself in my ability to identify as an individual that is not ensnared in alcoholism, but unfortunately am an individual that was highly tormented by alcoholism. Through observation of the group and how it processed, as well as identifying how I felt as a new attendee, I was able to understand why self-help, support groups are so vital for individuals in recovery. I finally realized, I too am in recovery.
Physicist in the 1900 first started to consider the structure of atoms. The recent discovery of J. J. Thomson of the negatively charged electron implied that a neutral atom must also contain an opposite positive charge. In 1903 Thomson had suggested that the atom was a sphere of uniform positive electrification , with electrons scattered across it like plum in an pudding. (Later known as the Plum Pudding Model)
The Trinity Project was a project conducted to test the effects of a nuclear weapon. The Trinity nuclear device was detonated on a 100-foot tower on the Alamogordo Bombing Range in south-central New Mexico at 0530 hours on 16 July 1945. (Rohrer, 1995-2003). This project was organized by the Manhattan Engineer District (MED). This organization worked diligently planning and coordinating all of the logistics for the groundbreaking event. From 1945-1946 over 1000 personnel either worked or visited the test site. The United States was trying to gain nuclear proliferation throughout the world so this project was necessary for our enemies to see the devastation of a nuclear blast.
KANSAS CITY STUDY- The Kansas City experiment was the first large-scale scientific study of law enforcement practices. Sponsored by the Police Foundation, it focused on the practice and preventive patrol. The second Kansas City study focused on “response time.” The second study uncovered that most reports made to the police came only after a considerable amount of time had passed. Therefore, the police were initially handicapped by the timing of the report 143. Importance- The Kansas City study was first scientific study of law enforcement, laying the foundation of law enforcement scientific studies.
* It was almost impossible to tell when the Alka-Seltzer tablet had dissolved, each time the experiment was done. This was a huge problem for the experiment as this could have totally caused problems to the experiment. A special type of detector apparatus, which bleeped when the correct amount of Alka-Seltzer tablet dissolved, could improve this, each time the experiment was done.
This is because of experimental error that prevented the experiment from being an isolated system and thus the Law of Conservation of Momentum could not be executed. Plagiarism Report and Declaration. Bibliography:.. 1. What is the difference between a. and a. M. Mann. a.
Sant, Joseph (2017). Francesco Redi and Controlled Experiments. Retrieved from http://www.scientus.org/Redi-Galileo.html on Oct 30, 2017.
Some time in July of 1947, a mysterious flying object zigzagged across the skies of New Mexico. Within twenty-four hours the object disappeared from radar just as mysteriously as it had appeared. It was last seen in a small town in the middle of the Arizona desert, it’s name, Roswell.
The largest and most powerful particle collider in the world, based in CERN on the border of France and Switzerland, it is a huge undertaking. It is built to assists the scientists in discovering what the Earth is made of; it also plays a crucial part in resolving many theories by scientists. It is a 27 kilometer ring with super magnets that help the particles speed along the way. Some people also argue that it’s a machine that could possibly be dangerous, because it has the capability of creating small BLACK HOLES! “One way or another, it's the world's largest machine and it will examine the universe's tiniest particles. It's the Large Hadron Collider (LHC).”
The Roswell Incident, which enlightened our minds to the capacity of excepting all, has remained one of the most controversial issues today. In Roswell, New Mexico, 1947, a strange occurrence arises. An alien craft from outer space crashed in an open field. The issue lay still for almost thirty years, until the thought of a government cover-up arose.
In 1951, Solomon Asch carried out several experiments on conformity. The aim of these studies was to investigate conformity in a group environment situation. The purpose of these experiments was to see if an individual would be swayed by public pressure to go along with the incorrect answer. Asch believed that conformity reflects on relatively rational process in which people are pressured to change their behaviour. Asch designed experiments to measure the pressure of a group situation upon an individual judgment. Asch wanted to prove that conformity can really play a big role in disbelieving our own senses.
The momentum of all three trials was not conserved. The lack of an isolated system is the most probable cause for the failure of this experiment.
The next big step in the discovery of the atom was the scientific test that proved the existence of the atom. After the discovery of the atom we had the discovery of subatomic particles. With the discovery of the subatomic particles came the research, which came from experiments that were made to find out more about the subatomic particles. This research is how we uncovered that most of the weight of an atom is from its nucleus. With the gold foil experiment, tested by Ernest Rutherford, he discovered the existence of the positively charged nucleus. He proved this when the experiment was happening, a small fraction of the photons th...