here are all the GCSE physics required practicals for AQA first some tips that you should always keep in mind when answering a question on a practical in your exams remember that in many of these investigations there's an independent variable the thing you change a dependent variable the other thing that changes as a result which you measure and controls variables that could change but we keep them the same throughout in order to ensure that results are accurate always say what piece of equipment you use for each measurement don't just say measure the length of the object also add with a ruler or whatever you're using that's a mark in itself State the flipping obvious if you think surely they don't want me to put that put it down anyway you never know what marks you might pick up talk about the accuracy of measurements how will you reduce errors and uncertainties for example you get your eye in line with the measurement when using a ruler or measuring cylinder to reduce Parallax error another classic thing you should put down is multiple or repeat measurements or readings to calculate a mean from finally it's okay to write your answers in bullet point format in fact I recommend it as it helps you and the examiner keep track of how many different points are being made because I'm trying to fit lows in here you might see me write abbreviated points for the sake of brevity but when you write a point do it in full make sure you use proper English don't start going all tazan like saying heat liquid with fire more like heat the water gently on a gauze on a tripod over a buns and burner flame also don't forget that you can see me and others from mansbury science doing these practicals for Realties on mansbury education link is in the description let's go physics one specific heat capacity every material or substance has its own essence H C tells us how much energy is needed to raise the temperature of 1 kg of the stuff by 1° C we can find this for water or Metals by inserting an electrical heater into a beaker of water or a block of metal if it has a slot for it measure the mass and place a thermometer in it to get the initial temperature turn on the heater and we measure the temperature the dependent variable every 20 seconds say we should also measure the current and PD and the heater using an ameter and voltmeter respectively this is important as it allows us to calculate the power supplied to the heater and therefore the block we need to rearrange the equation to make shc the object so this is equal to energy ided by mass time temperature change now there are a couple of ways we can use our data with the equation the easy way we just multiply the power by the time in seconds to get the energy supplied to the block then divide by the mass times the temperature change to get the shc the crazy way that AQA has in the spec but I think they've realized how ridiculous it is and so you'll never see it in the exams but there's always the possibility that they'll spring it on you we multiply Power by every time again to get an energy at each point and plot the temperature against each energy for every time interval you learned it by the curve within a straight line we get the gradient of the linear part of this graph find the reciprocal of that which gives us the energy divided by temperature in our equation so then we just divide that by the mass and you have the shc yeah I don't think even AQA is that evil to actually use this physics 2 resistance of a wire we just want to see the relationship between length of a wire and its resistance we use constant hand wire as its resistance doesn't change much when it gets hotter which is what we want attach the wires using crocodile clips and cables to a battery an amiter in series to measure measure the current and a voltmeter in parallel to measure the PD change the distance between the two crocodile Clips to change the effective length of the wire measure this with a meter rule making sure the wire is Tau when you do this calculate resistance for each length by rearranging Ohm's law resistance is equal to voltage PD / by current plot resistance against length and you should end up with a directly proportional relationship that is a straight line that goes through the origin if you extrapolate the line of best fit physics 3 IV characteristics if we vary the PD across a fixed resistor measured with with a voltmeter in parallel with it the current through it will also change measured with an ameter in series we can achieve this by changing a variable resistor in series with the fixed resistor we also turn the battery round and do the same to get Negative values of PD and current to this will produce a straight line going through the origin showing that the resistance is constant the component is omic do this with a filament bulb and the graph will be a curve the current won't increase as much at higher PDS this is because the resistance increases with higher currents it's non- ohic hopefully you know this is because the temperature increases with a higher current in a metal the ions oscillate more increasing the frequency at which electrons collide with them making it harder for them to flow finally if you do this with a diode you only get currents for a positive PD as they only allow current to flow in One Direction we say they have a very high resistance in One Direction very low in the other physics four density this one often crops up in exam questions finding the density of objects or solutions to find the mass of any solid object just place it on a top pan balance if it's a regular object object say a cuboid or a cylinder you can measure its Dimensions with a ruler or verer calipers that has a higher resolution and calculate its volume from these then use the equation mass divided by volume to find the density for any irregular object like a stone or a lumpy thing for which we can't calculate the volume we use a displacement or Ure can fill it up with water to the spout lower the object down with string until submerged and collect the water displaced with a beaker put this into a measuring cylinder to get an accurate value for the volume of the object to calculate the density from again using the equation you can find the density of a solution by putting a measuring cylinder on a balance and zeroing then pouring in the solution allowing you to find the mass and volume pure water has a density of 1 G per cm cubed so if you find that the density of say a salt solution is 1.2 G per cm cubed that means that the concentration of the salt is 0.2 G per cm cubed physics 5 Springs we can find the spring constant for a spring by fixing one end on a retor stand and a clamp and hanging slotted masses of increasing Mass to change the the force on the spring that's our independent variable and measuring the extension that's our dependent variable the best way of measuring extension is to fix a ruler as close to the spring as possible with the zero Mark lined up with the bottom of the spring then just measure where the bottom of the spring goes to when it's stretched multiply the mass by gravitational field strength 9.8 every time to get the force block this against extension even though you might think the axis should be the other way round it makes it such that the gradient of the line gives you the spring constant in Newtons per meter or Newtons per centimeter if you Capt your extensions in centimeters this is where Hook's law FAL ke comes from where K is the spring constant this should be a straight line that goes through the origin showing that this is a directly proportional relationship physics 6 Newton's Second Law we want to verify Newton's Second Law FAL ma for equals masstimes acceleration we do this by attaching slotted masses to a trolley on a track or the slider on an air track with the string going over a pulley we let the masses fall which accelerates the trolley a flag on the trolley will pass through two light Gates or photo Gates and the computer or Data Logger will calculate the acceleration there are two Alternatives we can just use one light gate to get its final velocity and use Newton's equation of motion if you have no light Gates you can just use a stop clock to get the time taken to go a certain distance using another of Newton's equations we can again get the acceleration we change the force accelerating the trolley by removing masses but these must be placed on the trolley every time why well that's because the force of gravity is not only accelerating the trolley but also the masses themselves so we must keep the total mass constant get the force by multiplying the mass by G every time plot the force against acceleration and you should once more end up with a proportional relationship a straight line going through the origin as FAL ma the gradient of this line should be equal to the mass of the trolley and masses physics seven waves a few different variations here using a ripple tank you can just use light to project an image of the Waves onto a screen or piece of paper using a ruler you can measure the length of 10 waves say then divide by 10 to get the wavelength this is much easier if the oscillator making the waves is also connected to a strobe light so the waves appear stationary on the screen the signal generator that's driving the oscill should also tell you the frequency being used if you change the frequency the wavelength will change but according to the wave equation V equal F Lambda the wave speed V should remain constant that is unless you change the depth of the water you could also just count the number of waves reaching the end of the tank over 10 seconds if they're slow enough then divide by 10 to get the frequency Waves per second the other pack involves getting an oscillator AKA vibration generator to produce a stationary wave on a string with masses on the end over a pulley to provide some tension we might also use a bridge instead you need to vary the frequency until you get the simplest stationary wave formed on the string one loop at this point the length of the string to the pulley or the bridge is equal to half the wavelength of the wave using this with the frequency driving the oscillator we can again calculate wave speed physics 8 infrared absorption easy piec of this one just fill a lesli cube with hot water from a kettle it's got different surfaces on its four sides using an infrared detector or infrared thermometer we can detect how much heat is radiated from each side you'll find matte black is the best emitter of infrared where a shiny silvery Sur are the worst another P we can do is just have boiling tubes wrapped in different materials with a thermometer through a bung in the top of each have the Sun or a lamp shine on them and record their temperatures after a set time you'll find that matte black is not only the best emitter of infrared it's also the best absorber while shiny surfaces are the worst absorbers which makes sense as they reflect light well so it's also true for infrared physics 9 insulation only for triple heaven knows why it is it's easy peasy wrap beakers of hot water in varying thicknesses or types of insulation with lids and thermometers and record the temperature drop over a certain time that's it physics 10 we can find the refractive index of a glass or PPC block by placing it on a piece of paper and Shining Light from a ray box in at an angle use a pencil to draw around the block and Mark where the ray enters and exits the block remove the block draw the normal at 90° to the surface where the light entered put the zero mark on the normal and measure the angle of incidence and angle of refraction i and r repeat this for different angles of incidence calculating sin I divided by sin R for each test will give you the same value each time say 1.5 this is the refractive index of the material leave a like and a comment if you found this 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