AQA physics combined science

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momentum quantity. m principle; (> Ile a closed system the total Momentum before an event is exactly the same to the tota momentim after the event. momentum mommen mommentum total = zero The electroma flee womagnetic syve are electora do dysturbuxues They bravel as maustet energy man a source to an absorber. Radio waves 10tm - Im. wh's spectrum: Radio waves 10⁰m - Im waves red 10 m Micro Infra Visable x-rays Camma light m 10 M 107m 10-10 m wavelength decreases. and T Are all trausvese waves دا سكرين Microwaves Infrared Visable/Ultra X-rays Gravoma light violet Oscillate Perpendicular to the Direction of wansfer. the energy frequency increases. rays 10⁰ when they are in different mediums they will haver at different speeds J M are in a vacum when they they will all travel at the exact same speed. ↓ [3×10³ M 15 ] 3x/0³, This leads to refraction where the wave chans direction. what differentiates the electromagnetic waves is their wavelength and their frequency which are inversely related If one goes up, another goes down! → Radio waves have the biggest wavelength but smallest frequency. → Gamama have the smallest beat rays wavelength but Diggest frequency. biny Our eyes are only able to detect part of the spechtum, this is visabled light. ROYGBIV Ultraviolet + X-Rays Gramma Rays colour of the rainbow. Tanising DO NOT Forget! I damaging to our cells. 6 D Electromagnetic waves are everywhere. Radioactive decay to be ammited can GALE cause can Ultraviolet and X-rays Visable light all be emitted when electrons drop down levels. When the bond everfy When the bonds. vibrate can generate infared. gamma rays! holding molecules together tight Infraredt miLLE X-ray's in medicine X- rays can be used to diagnose some conditions. X-rays pass through soft but are by not too then used to check for fractures. absorbed objects that medical hones, teeth, and netal. so they are and dental profes X-ray photographs, formed, on photography film flake charge coupled devises (CCD₂) internal body parts. are used to examine your Motor effect: a A current carrying wire in the presence of magnetic field experiences a force. # Ø To experience a full force, the wire has to be at 90° Xivare) current -carrying wire. 1 inbetween HWB If we place this into magnets, it will create a force. a slight direction, the force won't be as great. <> If its at Ly If it's at the same direction. of the field, there won't be any force. Twe To find the direction of the force. Is Find the direction of the magnetic held. is find the direction of the current. Flemings left hand rule use Take your left hand, the index finger is the clirection of the magnetic beld. The middle finger is the direction of the The thumb is the direction of the force held I current. L by Thaming the wire. Har sashor Magnera Calculating the strength of the force. Force = B T x t Magnetic current length of wire density. Electrict Motor: ний m x from Clockari'se N matt → to and clockwise The forces rok the wire rotate so then unce it rotates the dire chion of the current + force changes. If we left it like this, it would keep rotating. it wouldn't ever turn 360° only 180° To fit this we need to change the direction eve by Lof the current hall turn I So the coll will then continue to rotatge in the same direction To each achieve this, we use the Split-ring commutator. G It swaps the positive and negative connechous every half turns - so the direction of the current. every half thin J forces acting on the foil will always be acting in the same direchon.. Terminal velocity: 76 velocity No Longer Melerating decelina hing remains constant O when an object first starts falling. is much larger than any air So there is a resultant force in a down ward, direction [ causing it to accelerate towards the ground] weight downl resistance uyuow As the object accelerate, velocity increases. As velocity increas resistance does well because there the cellsion some with - air be will more Unhl at air partile). point air resistance and are equal weight meaning the resultant force is zero. 6 Terminal velocity shown. 2) If you pull out your parishute your surface area increases, which causes the air resistance increase as it creates move to collision. So the resultant force will face upwards. But over time it slows down. So the resultant force and the weight be cause equal. Which creates the resultant force to become zero. Is Terminal velocity is shown. 14/10/22 pg.75 Riquie Pekan Rippler Tank light Microwares and infared. those absorbeck by water molecules ↓ microwave ovens. they heat up food. ↓ food contains lots of feater molecules, the energy that's made gets absorbed by water molecules the Nore water heats up. more quickly than one that has less water. arent those who absorbed by water molecules Used by communicas. -Satellites. [have to pass throug the earths etmosping Infared. [IR] (s Emitted from all objects that have thermal evergy. i This depends on the amount of the objects himpreture. The hotter the object, the more infared it amits. 1₂ Use. Infrared candera's [helps us see in the dank! 6 helps us spot living organisms. писи трани radiahou they! which areas that are not and cold. Animals would appear bright since they emitt lokal would be darker since they do not pmist? of infarared radiation. While their surrounding as much infarared radia hout. -D Uses of IR. Cooking Ovens & Grills : (By heating metals in very high temps. I is we can make the metal emit lots of infrared rachation. Which can then heat our food by transferring the heat energy. Infarared Rachation doesn't penetrate the Surface of the food like microwaves, which is why bread toasts in a toaster, rather becoming generally warmer. Like than in a microwade Electrical heaters! Use electrical energy to heat up the metal then it emits i farared radiation into" our surroundings. Microwaves + Infarared are only harmful to us in large quantiber, background radjabo doesn't really do us harm. But if we put living alls in a microwave. they will boil and be destroyed. any Radiowaves: 6 longest wavelength to Lowest frequency Electromagnetic spectrum 17 Made up of oscillating and magnetic fields. ↓ Generate them using electricity form of a alternating currents elechic a device called a is connected to a os cilcoscope. ↓ when the radiowares Allows us to see the frequency are generated, we can detect it again by different of the alternating current. freq. of the Determines ware using device called a reciever, which absorbs the energy, and generates whother alternating current which is displayed by a Ossilloscope. * This allows us to transfer information. transmitter which Communications long waves. ↓ Can be transmitted in huge distances. short waves. Long distances. but can't curve around the earth. Instead -London-Singapore they are very t reflected around Is They diffract the ionosplaire. Jaround bluetooth the curved surface of the earth." short walles. Short distanse INKA. TV and Fl audio ↓ have to directly have! from the trans- -mither too the rectiver. Phone The waves used to carry any type of signal are called carrier waves! The shorter the wavelength of the waves: -The more information they carry •The shorter their ranger The less they spread out. x-rays and Gamme Rays! to shortest wave length b₂ Highest frequency * Helps us view the internal structure of objects... x-rays firing x-rays to the persons body. 'recording! to This works because *-rays and re the ones that get through are dense mate huls like passes straight through are mostly air. 6 Intestines, lungs absorbed bones, kury parts that Staff wear when & hay s kad are aprop and leave the roon bejing fired Absorbs * film badges monitors. gamma rays and trays. how which radiation person exposed too.. to kill Gamma radiation can be used bacheria in food, which prevents food poison fand to sterilise surgical instrumentos can also b cancer but may cause to kill camer leffs [radiotherapy ] The T Atomic structures isotres & electrons shells. nachys Autrons Isotopes Protons -Posibvely charged • relative mass of I alpha #Around the hulkens are shells that contorin electrons -Relative mass of 2 2000* Smatter - holds a charge a negative An atom of the same number of proterns, but different number of neutrons. Only one or two of an elements isotopes aved stable. The other elements which are unsterh decay mor other ekment) by enitting radiation ↓ This is called radioactive decay Some thing that is that it cousas of nustable isotopes that masthe radioachire means леку The 9 types of nuclear radiation B beta 7 Gamma vurhous -D leceppo brain or Andme • Coordination centres the change and decides what needs to be done. Alpha Marka radiation. They are the Same as nucleys of a helium atom! + OC "Since relatively large alpha purbile! are easily stopped by collisions They are shomly Jonising because of their large size and Charge, which makes it easier for them to kholl Hectrons elections. off any atour they collide with. Beda Only Alpha parheles do not have any electron Charge their overn! "2+ They can't penetrate as far. can penerate few cm of particles. They re just elections which have a of De and have no mass! 4 And are obsorbed thin shut pager cherige One of the atoms nuctions into a proton and a electron. Since Beta particles are Thuy, they are moderately louising marately for intor matinals. preedy and pehehave would take some of aluming hr stop them. Ona several metres of air tr Stop them. 17 emission of a neutron TIF contains bror many a nute nucleus nuctions which makes ist unstable; it s can just throw out a welltron to increase it's stability. 4 Prachcal 14 -o Specific Heat Capacity. a substance is The Specific heat capacity of the amount of energy required to raise the temperature of 1kg of the substana by 1°C℃! Specific heat capacity of a regatable oil. Press zero. a Place a balance and (2) Add the record the mass of the oil Place a thermometer and intr the oil. 4 Wrap the beaker an mmersion heater in insulating insulating foam to reduce thermal energy transfer The surroundings. Connect jou le mere? beaker on oil and us how many joules of electrical energy pass Bates the immersion heater. change in thermal meter to the Time for thirty mins. (7) Read the rutal written on the jou le meter. (the number of joules of energyd fmal temp that pass inter the immersion heater 7 and of the oil. = Rearrange for specific heat capacity immersion heater mass x Speathe Capacity ichange in thermal x de temp.change. mas s tempreture change. Sources of inaccuvancy- Thermal energy passing Not a oil. Use insulator with a lower 4. thermal conductivity. U of thermal energy passing Lo Ensure that immersion henter is fully Submerged.... Incorrect reading Use out of the beaker into Thermal the oil of the mememe an electronic rempreture probe -energy. 4. Shir the oil. into the not being spread through Required Practicat Resistor & bartery voltme variable. 72579 D Gren'stor Current/PD) character's he Use the vo Herncetor to read the PD. across the resistur Uso the ammeter to read the current through the resistor. the voldmete, (7) Record these value Then we adjust resister and record the new readings on and am meter. Do this several know to a range of readings. the varie Then we switich the direction of the Pd has Both the voltmeter and the ammeter should we on resisterty the direction of the battery. now reversed how have negative values! (Then re we have a graph of the current against the potential difference like this current through. the resister is directly * The X -(Pd) proportional for the potential. difference. -D A resister is an ohmic condua see this if the temp of the is kept constant. to "flament camp" we we adjust the variable resistor and read buth the pd and the current. (3 we do this for a range of values with the battery in the forward and reverse direction. *In the case of a filament lamp, we get a graph (A)) like this: (Pd) the In this case current isn't proportional for the current. directly That is because when the current increass the sempreture of the filament lamp increas and the increased tempreture cot the resistance to increase es causes 2 extra resistor A (1) Extra desistor its needed, because diodes are very easily damaged by in high current. (1) The Ethra resistor will keep the current. relatively low and protect the diode. current (3) Because the will be low, we need a very sensitive ammeter ↓ This is called a "miliammeter." • We adjust the variable resistor A number of himes & record the pd and current. They are do this with the battery in a forward and backwards motion! a by The results, in (A) J graph look like: we only get. current when fod) the potential dif is around 0.60.8 volts. 06v As pd increases beyond 1 this point, the current rises sharply. no with a diode we don't get any put or current if the pet is reversed that's because in a refverse direction, the diade a high resistance. has For a Substance to change state must T energy be transferred to or from the substance, this "called "catent heat." energy Units In Physics: (¹) Units for elastic putenhal energy. Joules (2) what are the units for change in thermial (3) energy Joules (4) what are the units for work clone - doules. (s) what are the units for volume -cm³ what are the mass - (1) what are the quits for granizational held shength - Nity (8) What are the units for energy transferred - Joylts (9) what are the units for Resurance -ohms. are the units for spring constant - N/m (10) what (1) What ние the (12) What are (13) what units for specific heart capacing (/y() units for charge ( columbs - () whits for specific lantent heat. (J/kg) (17) what are the units for speed (m/s), (is) what are the units for height (m) is measured in (s) (16) Time (11) ma are the units for density (xg/m³) 118) what are the units for kine he energy, (soules) (19) what are the units for grantahonal potenbal everyy (joules) (20) Power - (Warts) (21) what the units. in P.1) (Wolts.) (22) What are the (23) what are units in force (N) the units for momentum (xg m/s) my (24) what are (25) what are (26) what are the the units for distance (m the units for period (s) units for aculeration (m/s²) (27) what are the units for frequency (Hz) (28) What are the nurts for change in velocity (nd) (29) what are the units for length (m) the (30) What are the units for final velocity (m/s) the units for wavelength (mm) (32) what are the units for initial velocity (51) what are magnetic flute 6) (M/S) (38) what are the units for density (T) - Tesla. (39) Duits for extension (m) (90) what are the units for temp.. change (°C) (41) what are the units of current (Amps) are the units of weight (N) (42) what [x1000] m kilograms 1 kilometres [1000] [xx000] [+1000] grams 1000 metres. Secto Scalar quanh ryes have no direction. Examples include magnitude but speed 4 Vector quantities Examples include and momentum. Required practical :10 Infrared! Hot surfaces. the human have mhay nimde and direcho accator velocity weight emit intocared radiation but see this eye cannot We can use a leshie's cube to see how much infrared is wnitted from different surfaces. A leslie's cube has four different surfaces. A shing metallic surface. A while surface. A shing black surfice A motte black surface (not shiny ) First you fill the leslie's cube with hast we then point infrared deteck "water" at each of the four surfaces and record the amount of infarad emitted. It is very important that we keep the same distance between the leshie's cabe and the infrated detector. This makes the measurements. repeatub &. A Infrared emission. a (most) matt black Shing black White Shing metallic (least) If do not have use a the bullb painted black. infrared defect The resolution is the can be detected. an ther mome ter with But the resolution of the thermomethe is less than the infrared detector. smaliet change We may not be able to detect. difference between the surfaces using a that Large The infrared defector is more likely to detect the difference. How to measure the absorbance of infared in different surfaces. we place an infrared heater and on either side we have two metal plated, one place that is Shi metallic surface the other with matt Black faitf surfance. ку On the other side of the plates, we have used vase line to attach the drawing, Flon switch on the neater and start the the temp of the as they absorb infarad, takes for the living plated 9 metal the time it we record reases vaseline to me it and the drawing pins. his fall off. → The drawing pin falls off the black plate first more infarand. because Å F matte absorbs Matte black surfaces are much better than at un inudu and absorbing infrared: shiny metallic surfaces. Inforated heads w be reflected from shing metallic surfaces instead. Elechic circuits Current moves from the regénive to the positive end. Parallel circuits: Current in ļ The current in the branches adds up to the total current leaving the cell. Potential difference end of the ✓ Pd in parallel circuits : 6V it's shared. in Senes Circuits: A podenbal difference of I voit tells us that I Joule of energy is transferred for each coloumb of charge that is moving through the arcuit. ed=qv Pd is split between compon The total pd across both lamps, the same pd acrues the cull. & for parallel, the pd in each component is the same TIP TO DIAA -2x. ^6= Senes circulis so pd will be shared entlas extention (2l/ Physics Practicals: Ⓒ Swretching a spring (Equipment): clamp stand, two bouses and two clamps we now place a heavy weight on the clamp stand to stop falling over. Next we attack a metre rule and it spring weight (N) Spring constant is the same. 9 abanerke Ex (some you hurove the weight (N) weight, the extension. returns to zero. | pointer. The spring is elastic because if add too much docs] google. weight the graph will look like this. In this case, we overstretched the spring, the spring will still have extension if we book a ok away the weights. ✓ Read the position of this pointer on the merr mler. This is the undretched length of the spring (the length with) no force attached.) Ⓒ) Then we hang 1 N weight on the spring, then read the new position, (3) Continue A adding IN weights on the springs and reading. the position. & Then work out the exten produced by adding each neight; to do that, subtract the length of the unstretched spring from each reading. Scientists call this inclassic. deformation, by over streking 7 the spring we have exceeded the Umit of proporn muality. Acceleration We have a toy. car attached to a piece of sming. The string is looped around the pally pulley and the other end of the spring is attached to a 100g hass. The weight of the mass will provide a force acting out the hoy car. We also need a timer, we draw chalk lines at equal intervals eg every hy starting point. When we at the star 10cm. we hold the are ready we let of the car до GEV 60cm Roum HE Because that is a resultant force acting through the string the car will accelerate along the bench. We need to record the time that the car passes each distana If the car is acceleresting, rapidly it's difficult to record 7 1 Marker. an accurate bone. We repeat the experiment. but decrease the amount of mass on the end of the string. So the force is decreasing. The object is actually the my car, the string and the mass on the end of the as it's all connected smug rogether. 2) Instead record the experiment on a phone 16 you take some of the muss from the spring, you then bransfer it onto the car, so the overall mall is the same. Resistance & columb of charge through The resistance tells us how much energy is required to a component.. to the potential. resistor Current through is directly proportional difference. The resistance is constant. The resistance does not change of we increase the current. This kind of resister to a ohmic conductor. The resistance will only stay constant if the tempe is constant. Resistance of a filament lamp: ""Plament" - very fire wire. In u filament lamp a causes it to glow! As the Pd increases the current. no linger increases as much. high electric current flows. Pd There is so more energy is needed to push the current through the filament more collision, through pash it, which Resistance isn't directly proportional becau Current isn't directly. proportional to potential difference, that's because the filament becomes hot ← vibrate more. J This raises the tempretur the atoms in the filament The blament lamp isn't a ohmic conductor.. Diodes and LEDS DIODE: no current in reverse LED'S direction - Bliocles are useful for convulling the flow of curent in Circuits. DRAMM MALM LDR] Coment current in forward direction Pd fet • In dark Only allows current to flow in the forward direction ↑ LED gives off light when a current flows through.. The current through the diode Flows in one direction. only. It's extemely energy-efbuent Source of light. & Current through a resistor is directly proportional to the To takes very porennal diffference) little energy fr J pass through the LDR. That's because the diede has a very high. resistance in the reverse direction conditions, the LDR has a high resistance. • In the light, the resistance of LDR is low. very ohmic conductor. Is only of the temp is constant. Thermistor Z It's resistance of increases. thermistor decreased if the sempreture | low temp - high resistance. temp піды нтр I low resistance Alpha-Scattering and the Nuclear model: ↓ were beamed ut Geld foil was ring alpha particles. the gold foil. Alpha particles have a positive charge, the first thing Money saw was that the other particles pass Straight through the gold foil without changing. direction, Some Hnos, alpha particles was deflected deflected in othermes it changed direction as it passed through the gold boil and some bounced back. → Most of the alpha particles wert the shought through the gold Warom foil, therefore are mainly empty space. → Sing some of the particles ae was deflected, therefore, the centre of an atom must have positive chere a and that repelled the particles. → Since some banced straight back , the mass of the arom must be concentrated in the centre. We how call the cubal part of the nucleaus. an atom Radioactivity: Some iscrapes have an unstable nuclears, to become stable the nucleus gives 'ver out radiation. 2 Radioactive deany Radioactive decay is a random process the rate at which a To measure the crachioactivity. of radioustive source we Geiger -maller tube. a The count rate second by a detector. - Alpha particles is arom 7 9 A beta parbele nucleaus at 13 DH very high The act source of unstable nuclei doccrys. the same as a nuckans of measured is o² activity u Becquerel. [By] number of decays recorded each helium electron which is ajected from the speed. J It's formed inside the nuclears when a neutron changes intr proton and election. Half-life: The half-life of a radioactive iso hope is the time it takes for the number of пискi об thе потре in a dampи по have. object to nuckar radiation (alpha, beta, Irradiahion is exposing дашта ок пеurond). ак Radioactive contamination is when unwanted radioactive isotopes еnd uр он оних materials. () This is hazardous. A variable is anything that can change and be measured. Independent variables: the variable that is being changed Dependent variable: the variable being rested or measured during the experinant. ни