BGS IGCSE Physics EoY9 Exam Questions and Answers

What is a conductor? - ANSWER A material that allows electricity to flow through it What is an insulator? - ANSWER A material through which it is very difficult or impossible for electricity to flow What is current ...

What is a conductor? - ANSWER A material that allows electricity to flow through it What is an insulator? - ANSWER A material through which it is very difficult or impossible for electricity to flow What is current? - ANSWER The rate of flow of charge What usually carries the charge in electrical circuits? - ANSWER Electrons What is the equation that links charge, current and time? - ANSWER Charge = Current x time, Q = It What is the unit for charge? - ANSWER Coulombs, C What is the unit for current? - ANSWER Amps, A What component is used to measure current? - ANSWER An ammeter How is an ammeter connected in a circuit - ANSWER In series, with the component you want to measure What is voltage? - ANSWER The amount of energy transferred to each coulomb of charge that passes What is the equation that links voltage, energy and charge - ANSWER Energy = Charge x voltage, E = QV What is the unit of voltage? - ANSWER Volts, V What component is used to measured voltage? - ANSWER A voltmeter How is a voltmeter connected in a circuit? - ANSWER In parallel, across the component you want to measure What component do electrical devices use to show us if a circuit is turned on? - ANSWER A LED What is a series circuit? - ANSWER A circuit where all the components are connected in a single loop, the current has only one path to follow What is a parallel circuit? - ANSWER A circuit which has branches and junctions, the current can follow more than one path What is the rule for current in a series circuit? - ANSWER It is the same at all point around the circuit What is the rule for current in a parallel circuit? - ANSWER The total current before a junction = the total current after a junction What is the rule for voltage in a series circuit? - ANSWER The voltage from the power supply is shared between the components in the external circuit What is the rule for voltage in a parallel circuit? - ANSWER The voltage across each branch is the same as the voltage from the power supply. What is resistance? - ANSWER The opposition to the flow of current What is the equation that links voltage, current and resistance? - ANSWER Voltage = Current x resistance, V= IR What is the unit for resistance - ANSWER Ohms, Ω How do you work out the total resistance if resistors are connected in series? - ANSWER Add them together What is a diode? - ANSWER A component that only allows current to flow through it in one direction What is a variable resistor? - ANSWER A component which has resistance that can be changed What is a thermistor? - ANSWER A component whaich has a resistance that automatically varies with the external temperature What is a LDR? - ANSWER A component whaich has a resistance that automatically varies with the external light intensity What is the equation that links average speed, distance and time? - ANSWER Average speed = distance/time, v = d/t What is the unit for distance? - ANSWER Metres, m What is the unit for time? - ANSWER Seconds, s What is the unit for speed? - ANSWER Metres per second, m/s What does the gradient of a distance-time graph represent? - ANSWER The speed What does a steeper line on a distance-time graph tell us about the motion of the object? - ANSWER A higher speed What does a horizontal line on a distance-time graph tell us? - ANSWER The object is stationary What does a curved line on a distance-time graph tell us? - ANSWER The object is accelerating What is a scalar? - ANSWER A quantity with size but not direction Give 3 examples of scalar quantities - ANSWER distance, speed, mass, time, temperature, What is a vector? - ANSWER A quantity with size and direction Give 3 examples of vector quantities - ANSWER Displacement, velocity, force, acceleration What is acceleration? - ANSWER The rate of change of velocity What is the equation for acceleration? - ANSWER Acceleration = change in velocity/time, a = Δv / t What is the unit for acceleration? - ANSWER Metres per second squared, m/s^2 What is deceleration? - ANSWER Negative acceleration What does the gradient of a velocity-time graph represent? - ANSWER Acceleration What does a steeper line on a velocity-time graph tell us about the motion of the object? - ANSWER Higher acceleration What does a horizontal line on a velocity-time graph tell us? - ANSWER The object is travelling at a constant speed What does a horizontal line along the x-axis of a velocity-time graph tell us? - ANSWER The object is stationary What does a line with a negative gradient on a velocity-time graph tell us? - ANSWER The object is decelerating What does the area under a velocity-time graph tells us - ANSWER Distance travelled What is the equation that links acceleration, initial velocity, final velocity and displacement? - ANSWER (final velocity)^2 = (initial velocity)^2 + (2 x acceleration x displacement) What is weight? - ANSWER The force caused by gravity What is thrust? - ANSWER The driving force of an engine, motor or animal What is tension? - ANSWER The force in a material which is stretched What is electrostatic force? - ANSWER The force caused by static electricity What is air resistance / drag? - ANSWER The force caused when an object moves through a liquid or a gas