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الكلية كلية التربية للعلوم الصرفة
القسم قسم الفيزياء
المرحلة 1
أستاذ المادة فؤاد عطية مجيد
06/03/2019 12:39:06
We have always been curious about the world around us. Classical Physics – It constructs the concepts Galileo (15641642) and Newton’s space and time. It includes mechanics (rotation), light, heat (James Joule, Sadi Carnot), sound, electricity and magnetism (James Maxwell) Modern Physics – The application of special relativity, and particularly quantum theory, to such microscopic systems as atoms, molecules, and nuclei, which has led to a detailed understanding of solids, liquids, and gases, is often referred to as modern physics. Recording / Measurement – Compare with a standard length, mass, or time 2 1.1 Standard of Length, Mass, and Time The International System of Units: SI system: meter, kilogram, second Appendix A (The English System) 1 inch = 2.54 cm, 1 ft = 30.48 cm 1 mi = 1.609 km 1 lb = 0.454 kgw 1 atm = 14.7 lb/in.2 (PSI) = 760 mmHg = 101325 Pa (N/m2) ~ 1 kgw/cm2 The English system of measurement grew out of the creative way that people measured for themselves. Familiar objects and parts of the body were used as measuring devices. For example, people measured shorter distances on the ground with their feet. Length: Distance traveled by light in a vacuum during a time of 1/299 792 458 second. Give the correct length measurement for the left and the right rulers. 3 Time: Atomic clock: 9 192 631 770 times the period of oscillation of radiation from the cesium133 atom. Scientists have manufactured the world s smallest atomic clock, with inner machinery about the size of a grain of rice. Requiring very little power to run, the device loses only one second every 300 years and could one day provide precise timekeeping for portable applications such as wireless communication devices and Global Positioning System (GPS) receivers. Like other atomic clocks, the new design relies on the natural vibrations of cesium atoms, which “tick” 9.2 billion times each second. John Kitching of the National Institute of Standards and Technology and his colleagues trapped cesium vapor inside a chamber that is probed by a tiny laser, resulting in two electromagnetic fields. The team then adjusted the fields until the difference between them equaled that of the energy levels within the cesium atoms, causing the atoms to stop absorbing or emitting light. An external oscillator was then stabilized against the natural resonance frequency of cesium. “The real power of our technique is that we re able to run the clock on so little electrical power that it could be battery operated and that it s small enough to be easily incorporated into a cell phone or some other kind of handheld device”, explains Kitching. “And nothing else like it even comes close as far as being mass producible.” Mass: Kilogram is defined as the mass of a specified platinumiridium alloy cylinder kept at the International Bureau of Weights and Measures at Sevres, France. Radio Controlled Exact Set Atomic Projection, Alarm and Wall Clocks from Oregon Scientific, Casio, La Crosse Technology and more. Radio controlled clocks or "Atomic Clocks" keep perfect time by automatically synchronizing to the radio signal emitted from the U.S. Atomic Clock in Colorado. Radio controled clocks reset daily to the split second, and adjust automatically to Daylight Savings Time, Leap Year and Time Zone Changes. 4 You Must Know: Length: Mean radius of Earth: 6400 km, 6.4 x 106 m Diameter of a hydrogen atom: 1010 m, r = 0.529 angs Diameter of a proton: 1015 m Mass: Human: 7 x 101 kg Hydrogen atom: 1 * 103 / 6.02 * 1023 = 1.67 * 1027 kg Time: One day: 8.64 * 104 1018: atto 1015: femto 1012: pico 109: nano 106: micro 103: mili 103: kilo 106: mega 109: giga 1012: tera 1015: peta Density and Atom Mass Density: ? = m / V Gold: 19.3 * 103 kg / m3 = 19.3 g / cm3 5 Lead: 11.3 * 103 kg / m3 = 11.3 g / cm3 Copper: 8.93 * 103 kg / m3 = 8.93 g / cm3 Aluminum: 2.7 * 103 kg / m3 = 2.7 g / cm3 Example: A solid cube of aluminum has a volume of 0.200 cm3. It is known that 27.0 g of aluminum contains 6.02 * 1023 atoms. How many atoms are contained in the cube? 1.2 Matter and Model Building Quarks: up, down, strange, charmed, bottom, and top You should develop a process of building models as you study physics. 1.3 Dimensional Analysis vf = vi + at v has a dimension of L / T a has a dimension of L / T2 Quantity Symbol Dimension Area A L2 Volume V L3 Speed v L/T Acceleration a L/T2 Force f ML/T2 Pressure p M/LT2 Density d M/L3 6
1. Express the number in scientific notation, with the multiplier of the power of ten between 1 and 10. 2. If the multiplier is less than 10 = 3.162 (the square root of ten), the order of magnitude of the number is the power of ten in the scientific notation. If the multiplier is greater than 3.162, the order of magnitude is one larger than the power of ten in the scientific notation. 102 ´103 = 100´1000 =100000 =105 = 6.02´1023 A N Example: In 12g of carbon, there are A N carbon atoms. If you could count 1 atom per second, how long (in years) would it take to count the atoms in 1 g of carbon? 6.02´1023 /12/1(atom/ s) /86400/365 = 1.59´1015 0.0086 ~ 102 1.6 Significant Figures The significant figures include the first estimated digit. 7 Rule: multiplication & division – The number of significant figures in the result of multiplication or division is no greater than the least number of significant figures in any of the factors. 2.00 * 6.10 = 12.2 2.00 * 6.112 = 12.2 2.00 * 6.1 = 12 Rule: addition & subtraction – The result of addition or subtraction of two numbers has no significant figures beyond the last decimal place where both of the original numbers had significant figures. 1.001 + 0.003 = 1.004 1.001 + 0.2 = 1.201=1.2 Measurement Number of Significant Digits Distance between Markings on Measuring Device 142.7 g 4 1 g 103 nm 3 10 nm 2.99798 x 108 m 6 0.0001 x 108 m Example: A rectangle has a length of 3.21±0.02 m and a width of 2.8±0.1 m. Please calculate the area.
المادة المعروضة اعلاه هي مدخل الى المحاضرة المرفوعة بواسطة استاذ(ة) المادة . وقد تبدو لك غير متكاملة . حيث يضع استاذ المادة في بعض الاحيان فقط الجزء الاول من المحاضرة من اجل الاطلاع على ما ستقوم بتحميله لاحقا . في نظام التعليم الالكتروني نوفر هذه الخدمة لكي نبقيك على اطلاع حول محتوى الملف الذي ستقوم بتحميله .
