Science Reviewer 1st Trime PDF
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This document provides notes on physics topics, including forces, energy, and waves, suitable for secondary school pupils. It covers concepts like Newton's laws of motion, potential and kinetic energy, and properties of waves.
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Lesson1:ResisttheChange(p.3-6) Force – Any pushorpull Appliedforce – Force that is applied through directpushing or pulling Gravitationalforce – Exerted by gravity Normalforce – Force that is perpendicular tothesurface anobjectis in contact with. Elasticforce – Present in springs ...
Lesson1:ResisttheChange(p.3-6) Force – Any pushorpull Appliedforce – Force that is applied through directpushing or pulling Gravitationalforce – Exerted by gravity Normalforce – Force that is perpendicular tothesurface anobjectis in contact with. Elasticforce – Present in springs Tensionforce – Present incables,strings,cords,and othersimilar materials. Frictionalforce – Impedes motion. IsaacNewton Born on December 25,1642 Developed the3 laws of Motion Developed thelaw of universal gravitation Madediscoveries in thefield of infinitesimalcalculus 1st Lawof Motion: LawofInertia States that a body atrestwill continue to beat rest unless acted on by a netexternalforce. Inertia – Tendency of a body toresist any change inits motion. Lesson2:EmbracetheChange(pp.10-13) 2nd lawof Motion: Lawofacceleration -States thatacceleration is directly proportional to the force and is inversely proportional to the mass F = mx a F = Net external force in Newtons (N) m = Mass in kilograms (also grams) (kg) a = Acceleration in meter per second squared (m/s^2) Lesson3:EqualbutOpposite(p.17-21) 3rd Lawof Motion: LawofInteraction/LawofAction&Reaction- Thisstates thatforeveryaction,thereis an equal and opposite reaction. GalileoGalilei Born on 15 February 1564 Italian philosopher,astronomer,mathematician,and physicist. Coined theword “ friction” Lesson4:ConstantlyRoundandRound(pp.23-26) Uniformcircularmotion- Type of motion thatallows anobjecttofollowa circular path whilemaintaining a constant speed. CentripetalForce -Also known ascenter-seeking force,comes from the word century which means center. Centripetalacceleration -Forcedirected to the centre. a = v^2/r a = Centripetal acceleration measured in m/s^2 v^2 = Squareof thevelocity measured in m^2/s^2 r =Radius of thecircular path measured in m Period – Theamount of time needed to complete1 revolution or rotation; measured in seconds (s) Frequency -Number of rotations or revolutionper unittime;measured in Hertz (Hz) orrevolution persecond (rev/s) JohannesKepler - Born on December 27,1571 - Born inGermany - Developed the3 laws of planetary motion 1. Theplanets movein elliptical orbits,with thesun inthecenter 2. Thearea law 3. Theharmonic law Lesson1:Work,Work,andAway!(p.35-39) Displacement -How far anobjectis from where itstarted. Power – Rateof doing work P= W / t P = powerin watts (W) W = workin J t =time ins Work -Product of forceand displacement in thedirection of theforce. W= F x d W = work in Joules (J) F = force inN d = displacementin m JamesPrescottJoule -In 1843, determined theamount of work required toproduce a unit of heat. Lesson2:EnergyforYouandMe(p.43-47) Energy -theability to dowork Potential energy -energy possessed by an object by virtueof its position. PE = mx g x h PE= potential energy in J m =mass inkg g = magnitudeof the acceleration due to gravity,which is equal to 9.8 m/s^2 h = height inm Kineticenergy -energy present inmoving objects KE = ½ mx v^2 KE= Kinetic energy inJ m =mass inkg v= speed in metersper second (m/s) Lawofconservationofenergy -states that energy is neither created nor destroyed butis converted from one form to another. Lesson1:TheNatureofSound(pp.54-55) Sound – Produced by vibrations 1. Pitch – The perception of frequency of sound. Frequency is the number of periodic compression & rarefaction cycles 2. Amplitude/Loudness– Themeasure of theenergy of vibration 3. Speed – Which sound waves travel through themedium 4. ReflectionofSound – When sound waves hita surface of a solid, it bouncesback 5. Timbre – Used to differentiatesounds of thesamefrequency. Wave – Any form of disturbancethatcarries energy from one place to another. Mechanicalwaves – Requires a medium for transmission Electromagneticwaves – Does not requirea mediumfortransmission 1. Transverse -The direction of the particles is perpendicular to the direction of the motion of the wave’ s propagation 2. Longitudinal- Thedirectionof theparticles is paralleltothedirection of themotion of the wave’ s propagation 3. Surface- Theparticles travel in acircularmotion. Crest – Highest point of a wave. Trough – Lowest point of a wave. Wavelength -Thedistance between two consecutive crests or troughs. Amplitude -Theheight of the wavefrom therest position tothecrestortrough. Restposition– The baselinelevelof the medium when there are nowaves Compression – Where molecules are compressed or wherethereareshorter wavelengths. Rarefaction – Wheremolecules arestretched or spread out. Wavelength- Thedistance between two consecutive compressions or rarefactions. Amplitude -Themaximum distance the particles move fromtheir rest position,indicating energy. Restposition Kulintang -Composed of five to nine small gongs arranged horizontally. This instrument is played by hitting thesmallgongs. Palendag- Means “ wailing” or“ crying for grief” , is thebamboofluteused in Maranao. Itis played by blowing through it. Palipal- Madeof bamboo,cuttohaveopenings particularly at the middleparts of thebamboo. Played by shaking. Dadabuan- An instrumentthatlooks like a goblet. It isplayed using 2 sticks to tap it,itis famous among Mindanaoans. Kutiyapi/Kudyapi- Aninstrumentwith only twostrings. This instrument is used by the Maranaos and Manobos. Hegelung -A 2-stringed lutewith9 frets. An instrument played by theT’ bolisin Southern Mindanao. Alexander GrahamBell Born on March 3, 1847 Born in Edinburgh,Scotland Filed a patentdescribing soundsin 1876 justhours Elisha Gray filed his caveat fora similarmethod. Awarded patency bythePatent officein thesameyear. Lesson2:SoundandTemperature(p.62-65) v = 331m/s + (0.6m/s ° С)T v= Thespeed of sound in m/s T = Temperaturein ° С GiovanniLudovicoBianconi Italian doctor Demonstrated in1740 that, as temperatureincreases,thespeed of sound alsoincreases. Lesson1:WhatisLight?(p.73-76) Light -An electromagnetic wavethatcan travel even without a medium. It is both a waveand a particle ChristaanHuygens - Dutch mathematician - Developed the wavetheoryoflight - Invented the pendulumclock - Discovered the trueshapeof thewings of Saturn. 1. Reflection -Theproperty of awavethatrefers to the bouncingback of waves. 2. Refraction -The bending of light when it passes through differentmedia. 3. Diffraction -The bending of a wavewhen itpasses through a gaporaroundedges. 4. Polarization -Theproperty of a light wavethatallows an unpolarizedlight tovibrateortofocus in One Directionoron a singleplane. Lesson2:WhatistheLengthofthatColor?(p.79-83) Visiblelight – Arangeof frequencies the human eye can detect. Radiowave – Awaveemitted byradio stations thatis picked up by radios. Used in long distance communications. Microwave - Common applicationsincludecommunication and cooking. Infrared -Used in detecting counterfeit money. Used in transferring information and data between phones,in night vision devices,and in thermalscanners. Visiblelight – Lightthatis detectable by humaneyes. Ultraviolet -Ultraviolet radiation is emitted by the sun. X-ray -Used to take animage of your bones and lungs. Used indetecting diseases. Gammaray -Currently used in the field of medicinefor curing tumours Whenlight passes through a prism, it refracts;it'scolours of differentfrequencies are bent. Red – Has thelongest wavelength and the least energy. Violet – Has theshortest wavelength and themost energy. MaxKarlErnstLudwigPlanck - German theoreticalphysicist - Originated the quantumtheory - WontheNobelprizeforphysics in 1918 Lesson1:ItsGettingHotinHere(p.88-90) Temperature -The averagekineticenergy of a system. Itcan be measured in Celsius,Fahrenheit,Kelvin,and Rankine. Heat -Energy intransit Thermal equilibrium-Thestateof balance. Hotterobjects stop fromgiving off heat when both objects reach thermalequilibrium. AndersCelsius - Swedish astronomer - From Uppsala,Sweden - Invented the temperaturescale. AKAthe centigradescale. Lesson2:TheEffectsofHeat(p.95-98) A. Absorbsheat 1. Melting – Solid > Liquid 2. Evaporation – Liquid > Gas B. Releasesheat 1. Condensation – Gas > Liquid 2. Freezing – Liquid > Solid C. Direct phasechange 1. Sublimation – Solid > Gas 2. Deposition – Gas > Solid Thermal Expansion -The tendency of amaterialtoexpand when heated.