در این سایت می تونید مجموعه همه ی فیزیک کارشناسی رو یک جا مشاهده کنید و با توجه به گراف هایی که در هر زمینه داره میتونید اطلاعاتتون رو در رابطه با موضوعات مختلف بالا ببرید.
Briefly defined, physics is the science that tries to understand the laws of nature and the relationship between energy and matter. However, it might be more appropriate to define physics as a way of thinking rather than as a profession. The field of physics trains students to take a logical, problem-solving approach in whatever situations they might find themselves. Physics students explore concepts and methods of science that can be applied in many different professional areas and research topics.
Physics deals with everything from subatomic particles to black holes and the overall structure of the universe. Physicists use mathematical formulas to try to explain their theories and make predictions. It is a science that has attracted and confounded some of the most brilliant minds of all time: Sir Isaac Newton, Albert Einstein, and Stephen Hawking, to name just a few.
But physics is also concerned with how things work on a more tangible level. The laws of physics are applied to fields such as engineering, communications, biology, and electronics. The development of technologies like lasers and semiconductors resulted from pioneering work in physics. Televisions, microwaves and digital cameras would not exist without breakthroughs in physics.
Physics is really the study of how the world works, and, it might be considered the most fundamental of all the sciences. The goal of physics is to develop theories that will summarize the laws of nature and lead to an understanding of why things work as they do. The basics of physics can be applied to most other sciences, and for that reason, a great many people use physics as a springboard into other fields of study or professions.
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Nearly 90 percent of all "physicists" are working in medicine, education, industry, or other professions. Physicists are in demand for their analytical skills in many financial, fund management and research roles, in law, as weather forecasters, computer programmers, and as physics and science teachers.
Job descriptions are difficult to quantify in this field. The physicist might work in a laboratory, designing materials for computer chips or smashing atomic particles. Physicists have orbited the Earth and explored the oceans. They also build instruments that diagnose disease; they develop better and more efficient fuels for cars and homes; they calculate the movement of Arctic glaciers, and they create smaller, faster electronic components for computers.
Some physicists in research and development, especially those employed at universities, help increase our overall scientific knowledge. More often, they conduct research for government agencies or for private sector companies to develop new devices for the marketplace. They also design equipment or find new uses for older technology.
Medical physicists have greatly enhanced the well being of patients through the application of physics. Such advances as computer tomography, laser treatments for cancer, and the X-ray have improved health care over the years and led to more effective diagnosis and treatment of medical ailments.
Those professionals who do actually become physicists most often work regular hours in a laboratory where they plan and conduct experiments, build models for study, and examine test results. But this work can extend beyond the laboratory. Often, physicists must report on their results in lectures or through academic papers. They also might be responsible for finding the grant money that funds their work. These efforts require extensive skills in oral and written communications.
Job openings in universities and industry are increasing, thanks partly to a wave of retirements by senior physicists who entered the job market in the early 1960s. However, growth in academic jobs for physicists is expected to remain slower than average. Physics majors will continue to be in strong demand in industry, especially in the areas of information technology and semiconductor technology.
Physics graduates tend to split evenly between the workforce and graduate school. More than half of those students who return to graduate school decide to major in physics or astronomy. After those, the most popular graduate programs are in engineering, math, medicine, law, and education. Just over a quarter of all physics graduates who earn a bachelor's degree go to work in the private sector. Other career options include high school teaching, government, and the military.
The answer most appropriate for this question is: anything she wants to do. However, while some physics majors go on to become professional physicists, the majority pursue careers in fields where they can put their knowledge to more practical applications. With their skills in problem-solving, mathematical reasoning, computer programming, and organizing and interpreting scientific data, physics grads can move into government and industrial jobs that require an ability to think logically and creatively. Physics majors are well-suited to jobs that require step-by-step problem solving using math skills and good observational and communicational skills.
A wide range of industries seeks physics graduates: telecommunications, industrial physics, hospital physics, electronics, computing, quality control testing, banking, insurance, teaching, management, technical sales, and the armed forces, for starters. Students who become physicists tend to specialize in one or more areas of physics, such as:
A student with an interest in physics and communications might consider telecommunications, television, image analysis, video recording, photography, laser technology, journalism, scientific writing, and publishing. Other non-technical careers in which physics majors have found success are law, business administration, sports, marketing, and business management.
Besides astronomy, space and earth science careers for physics majors include space technology, atmospheric sciences, energy and resources, and ocean sciences. Openings in environmental sciences and physics would include positions studying noise control, pollution control, conservation, radiation protection, and environmental monitoring.
Despite the important and intriguing specialties available to physicists, the vast majority of physics majors enter other professions. They may teach high school physics, perform research and development in private industry or in government labs, or lend their expertise to medical imaging, scientific book publishing, and scientific reporting. Physics careers can come from unexpected places. Insurance companies, for example, hire physicists to study the performances of the products they insure and make recommendations for reducing injuries and property loss.
A graduate with a master's degree in physics can do most of the above jobs but usually with a higher degree of responsibility and pay. They also have the opportunity to teach at community colleges. A PhD holder is more likely to become a university professor or researcher. Industries will also hire PhDs to oversee research projects for their companies and design new scientific instruments.
"I think that physicists can do pretty much anything. Our training can be applied to almost any activity, and it allows us to see things in ways that might not be obvious to others" [Simon Singh, science writer and broadcaster]
Physicists play a vital role in many technology based industries such as optoelectronics, nanotechnology, computing and renewable energy. Others work on investigating the universe; searching for extra-solar planets or looking for the remnants of the big bang. Others still go on to apply their knowledge in healthcare (medical physics), studying the processes of the Earth (geophysics) or the climate (meteorology).
The knowledge and skills that studying physics develops are important in other areas as well. Predicting future market behaviour is vital in finance, and so a physicist's ability to model complex systems is particularly valued in this sector, while a logical approach and ability to understand new technology is useful in law, for example, when patenting new inventions.
Physics provides a broad training in skills that are valued by all employers; an ability to grasp concepts quickly, a determination to find coherent answers, along with problem-solving, analytical, mathematical and IT skills. Even if you decide that you don't want to work in any physics-related industry after your degree, the skills and knowledge that you develop by studying physics will always help you in whichever area you go into. Studying physics at degree level is a good way of keeping your options open
The salaries of physics graduates are also well above the national average. Over a working lifetime, the average physics graduate earns 30% more than someone holding just A-levels. This compares favourably with the average for graduates in all subjects (23%) and is about double the advantage gained by studying subjects such as psychology, biological sciences, linguistics and history.
To find out more about careers from physics see the careers section
The Nobel Prize in Chemistry recognizes the development of super-resolved fluorescence microscopy. Much of this field can be traced back to the first detection of single molecules in solids.
The 2014 Nobel Prize in Chemistry recognizes the work of Eric Bertzig, Stefan W. Hell, and William E. Moerner, who developed techniques in super-resolved fluorescence microscopy. One of the first breakthroughs in this field was the optical detection of a single molecule inside a solid crystal by Moerner in 1989. Previously, single molecules were thought to be optically undetectable.
When researchers study a particular molecule, they typically collect data from a large number of those molecules, but this collective approach hides individual variations that can exist between molecules. A protein, for example, is constantly changing shape, so a snapshot of many proteins will be an average over all those different forms. Environment can also affect the way molecules behave. If a certain molecule is dispersed sparsely throughout a solid matrix, the frequency of a single line in its spectrum will vary from one molecule to the next because each one is influenced by different local defects in its immediate environment. This spread in frequencies, which is called inhomogeneous broadening, has been a problem for precision measurements. “Moerner had the revolutionary idea to eliminate inhomogeneity effects completely by just addressing one single molecule,” says Lothar Kador, Moerner’s postdoctoral associate at the time, who is now at the University of Bayreuth in Germany.
The single molecule in Moerner’s 1989 paper was a hydrocarbon called pentacene. Moerner and Kador performed absorption spectroscopy on a low concentration of pentacene molecules incorporated in an organic crystal and chilled to near absolute zero. At these temperatures, the pentacene molecules should have a very narrow absorption line at 593 nanometers, but this line is broadened by 1000 times due to inhomogeneities in the crystal. Although such broadening is usually a nuisance, Moerner and Kador found a way to use the effect to detect a single molecule. They tuned a laser to a frequency in the tail at the edge of the spectral line, where the number of absorbing molecules was expected to drop to one or very close to one.
To identify the weak signal from a single pentacene molecule, the researchers used two types of “modulation” that reduce the noisy background: The first was frequency-modulation (FM) spectroscopy, in which the laser frequency oscillates over a small range. The second modulation was an oscillation in the position of the absorption peak, which the researchers induced by applying either a time-varying electric field or a time-varying stress from ultrasound waves. Under this double modulation, the spectral signature of a single pentacene molecule was a combination of peaks and dips in the shape of a W. The team detected several of these W-shaped features at different frequencies. To verify that the observed signature was due to a single molecule, Moerner and Kador increased or decreased the modulation frequency of their FM technique. In response, the W feature expanded or contracted—as expected for a single molecule—rather than changing in a random way, as would be expected if the feature came from several absorbing molecules with a range of central frequencies.
The physics community wasn’t entirely convinced at first, says Michel Orrit of Leiden University in the Netherlands. The data contained a lot of noise, and many people still had doubts that single molecule observation was even possible with light. Most skeptics were converted a year later, however, when Orrit and a collaborator redid the experiment, but instead of absorption they detected the fluorescent emission from a single pentacene molecule [1]. Fluorescence became the method of choice in single molecule detection, since it typically generates less background noise than absorption studies, Orrit says.
Years later, researchers discovered fluorescent proteins whose emission could be turned on and off. Methods soon developed in which a complex structure, like a cell membrane, is labeled (or “tagged”) with a large number of these beacon-like molecules. By turning on the proteins only a handful at a time, biologists precisely map out the location of each tag. They then combine these different maps into a super-resolution image of the full structure. “When we started our work, we did not plan to build a super-resolving microscope,” Kador says. “But in the course of time it turned out that single-molecule detection is able to achieve exactly this.”
دانشجویان فیزیک و فیزیکدان های دانشگاه صنعتی اصفهان هستیم.