Grade 12 High School - General Physics 1 Notes

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GENERAL‌‌PHYSICS‌‌1‌ ‌ Coordinate‌‌systems‌‌consist‌‌of;‌ ‌
‌ 1. Fixed‌‌reference‌‌point‌‌O,‌‌called‌‌the‌‌origin.‌ ‌
Lesson‌‌1:‌‌Unit,‌‌Measurement,‌‌and‌‌Vectors‌ ‌ 2. Set‌‌of‌‌specified‌‌axes‌‌with‌‌scale‌‌and‌‌labels.‌ ‌
‌ 3. Instructions‌‌on‌‌labelling‌‌points‌‌in‌‌space‌‌relative‌‌to‌‌O‌‌and‌‌axes.‌ ‌
Physics‌ ‌ ‌
Most‌‌basic‌‌of‌‌the‌‌sciences‌‌that‌‌deals‌‌with‌‌the‌‌behavior‌‌and‌‌structure‌‌of‌‌ Cartesian‌‌Coordinate‌‌System‌‌or‌‌Rectangular‌‌Coordinate‌‌System‌ ‌
matter.‌ ‌ A‌‌point‌‌is‌‌labelled‌‌as‌‌(x,y).‌ ‌
‌ Positive‌‌x‌‌is‌‌to‌‌the‌‌right‌‌of‌‌O‌‌and‌‌positive‌‌y‌‌is‌‌upward‌‌from‌‌O.‌ ‌
Major‌‌Branches‌‌of‌‌Physics‌ ‌ ‌
Classical‌‌Mechanics‌ Relativistic‌‌Mechanics‌ ‌ Plane‌‌Polar‌‌Coordinates‌ ‌
Quantum‌‌Mechanics‌ Quantum‌‌Field‌‌Theory‌ ‌ (r,‌‌θ),‌‌where‌‌r‌‌is‌‌the‌‌distance‌‌of‌‌the‌‌point‌‌to‌‌O,‌‌and‌‌θ‌‌is‌‌the‌‌angle‌‌
‌ measured‌‌from‌‌the‌‌reference‌‌line,‌‌which‌‌is‌‌usually‌‌the‌‌positive‌‌x-axis.‌ ‌
Standards‌‌of‌‌Length,‌‌Mass,‌‌and‌‌Time‌ ‌ ‌
‌ Vectors‌‌A
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Common‌‌Units‌‌of‌‌Measure‌ ‌ Scalars‌‌have‌‌magnitude‌‌(number‌‌with‌‌a‌‌unit).‌ ‌
1. Systeme‌‌International‌‌(SI)‌ m,‌‌kg,‌‌s‌ ‌ Vectors‌‌have‌‌both‌‌magnitude‌‌and‌‌direction.‌ ‌
2. Gaussian‌‌System‌‌(CGS)‌ cm,‌‌g,‌‌s‌ ‌ ‌
3. US‌‌Customary‌‌System‌ ft,‌‌slug,‌‌s‌ ‌ ‌
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Seven‌‌Fundamental‌‌Quantities‌ ‌
1. Length‌ meter‌ m‌ ‌
2. Time‌ second‌ s‌ ‌
3. Mass‌ kilogram‌ kg‌ ‌
4. Electric‌‌Current‌ ampere‌ A‌ ‌
5. Temperature‌ kelvin‌ K‌ ‌
6. Amount‌‌of‌‌Substance‌ mole‌ mol‌ ‌
7. Luminous‌‌Intensity‌ candela‌ cd‌ ‌
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Prefixes‌‌of‌‌the‌‌Metric‌‌System‌‌(SI‌‌and‌‌CGS)‌ ‌
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Tera‌ 1‌‌000‌‌000‌‌000‌‌000‌ 10‌12‌ T‌ ‌
Giga‌ 1‌‌000‌‌000‌‌000‌ 10‌9‌ G‌ ‌
Mega‌ 1‌‌000‌‌000‌ 10‌6‌ M‌ ‌
Kilo‌ 1‌‌000‌ 10‌3‌ k‌ ‌
Deci‌ 0.1‌ 10‌-1‌ d‌ ‌
Centi‌ 0.01‌ 10‌-2‌ c‌ ‌
Milli‌ 0.001‌ 10‌-3‌ m‌ ‌
Micro‌ 0.000‌‌001‌ 10‌-6‌ u‌ ‌
Nano‌ 0.000‌‌000‌‌001‌ 10‌-9‌ n‌ ‌
Pico‌ 0.000‌‌000‌‌000‌‌001‌ 10‌-12‌ p‌ ‌
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Uncertainties‌ ‌
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Estimated‌‌Uncertainty‌ ‌
Percent‌‌Uncertainty‌ ‌
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Significant‌‌Figures‌ ‌
Number‌‌of‌‌reliably‌‌known‌‌digits‌‌in‌‌a‌‌number.‌ ‌
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Accuracy‌‌and‌‌Precision‌ ‌
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Accuracy‌ ‌
Closeness‌‌of‌‌the‌‌experimental‌‌values‌‌to‌‌the‌‌expected‌‌or‌‌true‌‌value.‌ ‌
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Precision‌ ‌
Closeness‌‌of‌‌the‌‌experimental‌‌values‌‌with‌‌one‌‌another.‌ ‌
Having‌‌more‌‌significant‌‌figures‌‌indicates‌‌more‌‌precision.‌ ‌
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Order-of-Magnitude‌‌Estimate‌ ‌
Approximate‌‌value‌‌of‌‌a‌‌quantity‌‌within‌‌a‌‌factor‌‌of‌‌10.‌ ‌
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Enrico‌‌Fermi‌ ‌
Italian-American‌‌nuclear‌‌physicist‌‌and‌‌Nobel‌‌laureate‌‌called‌‌this‌‌
estimation‌‌method‌‌as‌‌“back-of-the-envelope‌‌calculations”‌ ‌
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Coordinate‌‌Systems‌ ‌
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Locations‌‌in‌‌space‌ ‌
1. Points‌‌on‌‌a‌‌line‌‌can‌‌be‌‌located‌‌with‌‌one‌‌coordinate.‌ ‌
2. Points‌‌in‌‌a‌‌plane‌‌can‌‌be‌‌located‌‌with‌‌two‌‌coordinates.‌ ‌
3. Points‌‌in‌‌a‌‌space‌‌can‌‌be‌‌located‌‌with‌‌three‌‌coordinates.‌ ‌
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Lesson‌‌2:‌‌Motion‌‌in‌‌One‌‌Dimension‌ ‌ Lesson‌‌3:‌‌Motion‌‌in‌‌Two‌‌Dimensions‌ ‌
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Mechanics‌ ‌ Projectile‌‌Motion‌ ‌
Study‌‌of‌‌the‌‌motion‌‌of‌‌objects,‌‌and‌‌the‌‌related‌‌concepts‌‌of‌‌force‌‌and‌‌energy.‌ ‌ Motion‌‌of‌‌an‌‌object‌‌(projectile)‌‌that‌‌is‌‌thrown‌‌(projected)‌‌through‌‌the‌‌air.‌ ‌
‌ Only‌‌force‌‌acting‌‌on‌‌it‌‌is‌‌gravity,‌‌therefore‌‌there‌‌is‌‌a‌‌downward‌‌acceleration‌‌
Kinematics‌ ‌ due‌‌to‌‌gravity‌‌(-g).‌ ‌
Description‌‌of‌‌how‌‌objects‌‌move.‌ ‌ ‌
‌ Galileo‌‌ ‌
Dynamics‌‌or‌‌Kinetics‌ ‌ First‌‌accurately‌‌described‌‌projectile‌‌motion.‌ ‌
Deals‌‌with‌‌force‌‌and‌‌why‌‌objects‌‌move‌‌as‌‌they‌‌do.‌ ‌ Said‌‌an‌‌object‌‌projected‌‌horizontally‌‌will‌‌reach‌‌the‌‌ground‌‌the‌‌same‌‌time‌‌
‌ as‌ ‌an‌‌object‌‌dropped‌‌vertically,‌‌because‌‌vertical‌‌motion‌‌of‌‌both‌‌cases‌‌are‌‌
Displacement‌‌‌(Vector)‌ ‌ the‌‌same.‌ ‌
Change‌‌in‌‌position‌‌of‌‌an‌‌object,‌‌and‌‌how‌‌far‌‌it‌‌is‌‌from‌‌its‌‌starting‌‌point.‌ ‌ ‌
‌ Components‌ ‌
Distance‌‌‌(Scalar)‌ ‌ 1. v‌y‌‌ ‌continually‌‌decreases‌‌until‌‌reaching‌‌maximum‌‌height.‌ ‌
‌ 2. v‌x‌‌ ‌remains‌‌constant.‌ ‌
Velocity‌‌‌(Vector)‌ ‌ ‌
‌ Relative‌‌Velocity‌ ‌
Average‌‌Velocity‌ ‌ Velocities‌‌in‌‌different‌‌reference‌‌frames.‌ ‌
Magnitudes‌‌of‌‌average‌‌speed‌‌and‌‌average‌‌velocity‌‌are‌‌equal‌‌only‌‌if‌‌the‌‌ If‌‌along‌‌the‌‌same‌‌line,‌‌add‌‌or‌‌subtract‌‌the‌‌velocities.‌ ‌
motion‌‌is‌‌all‌‌in‌‌one‌‌direction.‌ ‌ If‌‌not‌‌along‌‌the‌‌same‌‌line,‌‌use‌‌vector‌‌addition.‌ ‌
Direction‌‌is‌‌signified‌‌by‌‌(+/-),‌‌and‌‌is‌‌the‌‌same‌‌as‌‌that‌‌of‌‌the‌‌displacement.‌ ‌ ‌
‌ Same‌‌Direction‌‌‌(along‌‌the‌‌same‌‌line)‌ ‌
Speed‌‌‌(Scalar)‌ ‌ Add‌‌or‌‌subtract‌‌the‌‌velocities‌ ‌
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Instantaneous‌‌Velocity‌ ‌ Different‌‌Directions‌‌‌(not‌‌along‌‌the‌‌same‌‌line)‌ ‌
Velocity‌‌at‌‌any‌‌instant‌‌of‌‌time.‌ ‌ Use‌‌vector‌‌addition‌ ‌
Magnitudes‌‌of‌‌instantaneous‌‌speed‌‌and‌‌instantaneous‌‌velocity‌‌is‌‌always‌‌ V‌AB‌,‌‌where‌‌A‌‌is‌‌the‌‌object‌‌and‌‌B‌‌is‌‌the‌‌reference‌‌frame.‌ ‌
equal.‌ ‌ ‌
Instantaneous‌‌and‌‌average‌‌velocity‌‌are‌‌equal‌‌if‌‌the‌‌object‌‌has‌‌uniform‌‌or‌‌ ‌
constant‌‌velocity.‌ ‌
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Position‌‌vs.‌‌Time‌ ‌
Average‌‌velocity‌‌of‌‌an‌‌object‌‌during‌‌any‌‌time‌‌interval‌‌is‌‌equal‌‌to‌‌the‌‌
slope‌‌of‌‌the‌‌straight‌‌line‌‌connecting‌‌two‌‌points.‌ ‌
Instantaneous‌‌velocity‌‌equals‌‌the‌‌slope‌‌tangent‌‌to‌‌the‌‌curve‌‌of‌‌a‌‌point.‌ ‌
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Acceleration‌ ‌
An‌‌object‌‌whose‌‌velocity‌‌is‌‌changing.‌ ‌
Instantaneous‌‌acceleration‌‌is‌‌the‌‌average‌‌acceleration‌‌over‌‌an‌‌infinitesimally‌‌
short‌‌time‌‌interval.‌ ‌
Deceleration‌‌is‌‌when‌‌velocity‌‌and‌‌acceleration‌‌are‌‌in‌‌the‌‌opposite‌‌directions.‌ ‌
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Velocity‌‌vs.‌‌Time‌ ‌
Average‌‌acceleration‌‌of‌‌an‌‌object‌‌during‌‌any‌‌time‌‌interval‌‌is‌‌equal‌‌to‌‌the‌‌
slope‌‌of‌‌the‌‌straight‌‌line‌‌connecting‌‌two‌‌points.‌ ‌
Instantaneous‌‌acceleration‌‌equals‌‌the‌‌slope‌‌tangent‌‌to‌‌the‌‌curve‌‌of‌‌a‌‌
point.‌ ‌
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Motion‌‌at‌‌Constant‌‌Acceleration‌ ‌
Instantaneous‌‌and‌‌average‌‌acceleration‌‌are‌‌equal.‌ ‌
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Free‌‌Falling‌‌Objects‌ ‌
At‌‌a‌‌given‌‌location‌‌and‌‌in‌‌the‌‌absence‌‌of‌‌air‌‌resistance,‌‌all‌‌objects‌‌fall‌‌with‌‌
the‌‌same‌‌constant‌‌acceleration,‌‌the‌‌acceleration‌‌due‌‌to‌‌gravity‌‌(g).‌ ‌
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Acceleration‌‌due‌‌to‌‌Gravity‌‌‌(g)‌ ‌
Varies‌‌according‌‌to‌‌latitude‌‌and‌‌elevation‌‌on‌‌the‌‌surface‌‌of‌‌the‌‌earth.‌ ‌
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