A Level Edexcel Physics Paper 1 Questions And Answers 2025/2026, Exams of Physics

Download A Level Edexcel Physics Paper 1 Questions And Answers 2025/2026 and more Exams Physics in PDF only on Docsity!

ρ ρ

A Level Edexcel Physics Paper 1 Questions And Answers 2025/2026 Newton's Third Law - correct Answlf object A exerts a force on object B, then object B exerts an equal but opposite force on object A Newton's Third Law pairs - correct AnswExample: An object exerts a weight of SON onto the earth. The third law pair would be that the earth would exert a NCF of SON on the object Conditions for Newton's Third Law Pairs to be true - correct Answ- Two Different Forces - Act on the same line - Same magnitude - Different objects - same time Potential Dividers - correct AnswA circuit that is used to only output part of the voltage provided Potential Divider equation - correct AnswVout/Vin = R1/R1+R2 Potential Dividers and thermistors - correct Answlf a thermistor is used as R1, as temperature decreases resistance increases and thus Vout increases as they are proportional, this can be used asa heating system to turn it on ifit gets cold enough Potential Dividers and LDRs - correct Answlfa LDR is used as R1, as light decreases resistance increases and thus Vout increases as they are proportional, this can be used for street lights to be turned on as light decreases Thermistor - correct Answa resistor whose resistance depends on the temperature of the thermistor As temperature decreases resistance increases LDR - correct AnswLight dependent resistor As light increases resistance decreases Rheostat - correct Answ When a variable resistor is used to control current Variable Resistor - correct AnswA resistor whose value can be varied between its minimum and maximum values. Variable Resistors and Potential Divider Uses - correct AnswA variable resistor can act as a potential divider to act as a continuous slider to increases or decrease Vout. ‘his can be used as a dimmer switch Magnetic Flux Density - correct Answa measure of the strength of the magnetic field. How densely packed lines of flux are equates to how strong a field is Measures in Tesla T Magnetic Flux - correct AnswThe total number magnetic field lines that pass through a surface = magnetic flux density x Area F = Force B = Magnetic field strength (density) I= Current L= length Angle at 90 degrees should just use F = BIL as sin90 = 1 therefore cos component will not affect the force Angle at 0 degrees will be 0 as sin0 = 0 Equation for a magnetic field on a moving charge - correct AnswF = BQV F = Force B = Magnetic field strength (density) Q = charge V = velocity Equation for a magnetic field of a moving charge not at 90 degrees to the field - correct AnswF = BQVsin(angle} F = Force B = Magnetic field strength (density) Q = charge V = velocity Angle at 90 degrees should just use K = BIL as sin90 = 1 therefore cos component will not affect the force Angle at 0 degrees will be 0 as sind = 0 Fleming's Left Hand Rule - correct AnswFirst Finger Field seCond finger Current thuMb Motion Relativistic Effects - correct AnswOnly when objects approach the speed of light do our observations begin to depart measurably from the predictions of Newtonian Physics Muon Decay and Relativistic Effects - correct AnswMuons are created a few kilometers above the earth yet for the time they should take to get here they would decay before they hit the surface But they do hit the surface, this is due to relativistic effects as muons are going close to the speed of light The doppler Effect Model Answer - correct AnswAs something that is moving is giving out a wave its frequency can change as it is being compressed by the moving object and therefore to a relative observer the frequency appears higher Cosmological Red Shift Model Answer - correct AnswAs the universe expands, galaxies are moving away from us the relative observer. The light these galaxies give off ir also redshifted so that its wavelength increases Cosmological Redshift Equation - correct Answz = AWavelength/ Wavelength = Velocity/Speed of light Resolving vectors - correct AnswPlace vectors together For a right angle triangle sides can be calculated using Pythagoras Other triangles can be calculated suing cosine Internal Resistance - correct Answresistance inside the source of electrical energy - loss of PD per unit current in the source when current passes through it Electromotive force - correct Answ'l‘he electrical potential energy transferred from other forms, per coulomb of change that passes through the source Energy transfer EMF equation - correct AnswWork Done = Charge x emf Emf Equations - correct AnswE = V + IR E=IR+Ir E=[(R+n E=emf V = Voltage I= Current R = resistance r= internal resistance Lost Volts - correct AnswThe potential difference across the internal resistor of a source of e.m-f. emf = V + lost volts ‘Lhe difference between emf and pd - correct Answemf is the energy transferred from chemical to electrical pd is the energy transferred from electrical to other forms eg. light, heat emf is transfered from other forms where as pd transfers to other forms How to increase induced emf - correct Answ- Use a stronger magnet - use a coil with more turns -use a coil with greater cross sectional area ~ Make relative movement between magnet and conductor faster Baryon - correct AnswA hadron consisting of three quarks Meson - correct AnswA hadron consisting ofa quark and an antiquark Lepton - correct AnswAn elementary particle that have no internal structre Hadron - correct AnswA particle made up of quarks Lepton Examples - correct Answ1st gen electron 2nd gen muon 3rd gen tau Increasing 1-3 An object being hit off the ground at an angle horizontal distance travelled - correct AnswWork out horizontal component of inital velocity Use d = horizoncal velocity x time Effect of friction on projectiles vertical motion - correct AnswUpwards gravity and friction work together to slow down projectile Downwards friction goes against gravity slowing it Effect of friction on projectiles horizontal motion - correct AnswDrag forces oppose the motion, leading to horizontal deceleration Change in resistance with temperature model answer - correct Answ- Metals contain large numbers of free electrons - As these electrons move through the metal lattice they collide with vibrating metal ions - These collisions oppose the flow of electrons so the metal has a set resistance - When temperature increases ions vibrate faster and make it more difficult for electrons to pass through the lattice increasing resistance futher Faraday's Law - correct AnswThe magnitude of the induced emf is directly proportional to the rate of change of flux linkage Faraday's Equation - correct Answemf = coils x change in flux linakge / time taken Change in flux linkage can be calculated by multiplying the field strength and the area Lenz's Law - correct Answ'l‘he direction of an induced current is such that it will try to oppose the change in flux chat is producing it Lenz's Equation - correct Answls like faraday's but adds a negative sign emf = -coils x change in flux linakge / time taken An emf is induced - correct AnswWhen there is relative movement between a magnet and a coil Dropping a bar magnet through a coil - correct AnswAs the magnet enter the coil the flux linkage of the coil increases and an emf is induced As the magnet falls right in the middle of the coil there is 0 flux linkage and no emf induced As the magnet falls out of the coil the flux linkage decreases and emf is induced in the opposite direction Emf is equal to a area strip under the graph The second dip is narrower as the magnet is accelerating due to gravity Magnetic Braking - correct AnswWhen a driver activates the brakes a current is passed through coils. The spinning rotors cut through the magnetic flux and so eddy currents are induced in the discs The eddy currents slow so as to oppose the change producing them hence slowing the rotors and thus the wheels Contact brakes are still needed for the final slowing down as at slow speeds smaller eddy currents produce to small an effect Root Mean square value - correct Answa measure of the average amplitude inan AC graph wave rms value = peak value / root2 Current rms equation - correct Answlrms = 10/root2 Voltage rms equation - correct AnswVrms = V0/root2 Antimatter - correct AnswA “complementary” form of matter composed of particles that have equal but opposite charge and spin in opposite directions Conservation of charge baryon number and lepton number - correct Answn -> pre+X Find x Draw out the table of lepton, baryon and charge n>pte+X To balance the equation x must have a charge of 0, a baryon number of 0 and a lepton number of - 1. This is an uncharged anti-lepton and therefore must be an antineutrino Compare E and G fields model answer - correct AnswNewton's Law of gravitation vs coulombs law of charge: - Force is felt by objects with mass - Force is felt by objects with charge - Force is proportional to the size of the masses - Force is proportional to the size of charges - There is a gravitational field around mass - There is an electric field around charge - There is only one type of mass - But two types of charge - Force in mass is always attractive - In charge it can be attractive or repulsive - The constant of proportionality id G and it does not change - Charge’s is k and depends on the material - Gravitational force is weak unless a big mass - Electric force is very strong but not noticed as the charges cancel out in an atom - Both have force inversely proportional to the square of the separation Free Body Diagram - correct Answa diagram showing all the forces acting on an object Radial Electric Field - correct Answ Resitivity - correct AnswThe resistance of a sample of the material of unit length and cross sectional area Resistivity Equation - correct AnswR = pL/A R, resistance P, resistivity L, length A, cross section area What is the unit of resistivity? - correct AnswOm Drift Velocity - correct Answthe net velocity of a charge carrier moving in an electric field Derivation of drift velocity - correct AnswVolume of a wire = Ax | Lf there are n electrons per meter cubed. then the number of electrons in a wire = n x Ax 1 The total charge on an electron is ¢ then the total charge going through a wire is = nx Axl xe It takes an electron time t to travel through the wire and current is charge passing per second then I= Q/t = nAle/t, but L/t is velocity to I = nAve Drift Velocity Equation - correct Answl = nAve Uniform Field - correct Answ- Lines must be equally spaced ~ electric fields travel + to - - Magnetic fields travel N-S - Gravitational fields travel to mass Newton Equation - correct AnswF = ma F = ma derivation - correct AnswNewtons Law = F = k x (my-mu)/t k = 1 because 1 newton is the resultant force to cause a rate of change of momentum lkgms*-1 each second therefore F = change in(my)/t If mass stays constant F= m(v-u)/t Change in v over time isa ‘Lherefore F = ma Newcon - correct Answresultant force needed to give a mass of 1kg an acceleration of Lms-1 a=rw42 You accelerate towards the centre of the circle Capacitor - correct AnswAn electrical device used to store electrical charge. Capacitance - correct Answthe ability of a conductor to store energy in the form of electrically separated charges Capacitance equation - correct AnswC = Q/V Annihilation - correct AnswWhen an antimatrer and matter meet they destroy each-other and their is converted into energy Annihilation example - correct AnswWhen an electron and a positron meet they annihilate and release 2 gamma photons 2 are released to conserve momentum of two particles annihilating How new particles are created during annihilation - correct Answlf sufficient energy is available annihilation can produce short lived particles in order to conserve momentum as the energy is converted back into matter Pair Production - correct AnswHigh-energy photons can vanish creating particle and antiparticle pairs in their place Example of pair production - correct AnswA gamma ray can pair product into an electron and a positron A third particle such as an atomic nucleus or electron is often involved indirectly, this recoils carrying away some of the photon energy Particle tracks curvature - correct AnswThe higher the energy and speeds the particles are going the less they are deflected against a magnetic field Einstein's Equation - correct AnswE=mc*2 Energy and mass are equivalent In any system the coral amount of mass and energy is conserved Conversation of momentum - correct Answln a closed system, when two objects interact their total momentum in any direction remains constant provided that no external forces acts on the object in that direction Total momentum before interaction = - correct AnswTotal momentum after the interaction (provided no external forces are acting) 1d collisions in the same direction not sticking together - correct Answmv + my = my + mv 1d collisions head on collisions sticking together - correct Answmy - my = collective mass x v 1d collisions in the same direction sticking together - correct Answmv + my = collective mass x v 1d recoil - correct Answ0 = mv + my Gun velocity will be negative as it is going back