P2- Revision Questions Flashcards
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| 16300512728 | For electrical charge to flow through a closed circuit, what must there be? | Must be a potential difference | 0 | |
| 16300512729 | What is Current? | IS the flow of Charge | 1 | |
| 16300512730 | What equation links charge flow, current and time? | Charge Flow (C) = Current (A) x Time (S) | 2 | |
| 16300512731 | In a series circuit, is the value of the current the same at any point in the loop? | Yes | 3 | |
| 16300512732 | What equation links potential difference, current and resistance | Potential Difference (V) = Current (A) X Resistance (Ohms) | 4 | |
| 16300512733 | What does potential difference mean the same as? | Voltage | 5 | |
| 16300512734 | What does a current through a component depend on? | The resistance of the component and the potential difference across it | 6 | |
| 16300512735 | The greater the resistance of the component.... | The smaller the current for a given potential difference across the component | 7 | |
| 16300512736 | How do you connect an ammeter in a circuit? | You must connect it in series with the current flowing | 8 | |
| 16300512737 | How do you connect a voltmeter in a circuit? | You must connect it in parallel with the electrical energy (eg. Bulb) | 9 | |
| 16300512738 | What is an ohmic conductor? | A conductor which obeys Ohm's Law, and will have a positive gradient. | 10 | |
| 16300512739 | In some resistors, what happens to the value of R? | It remains constant | 11 | |
| 16300512740 | What happens to the resistance of a thermistor as the temperature increases? | Decreases | 12 | |
| 16300512741 | Give a use of thermistors | Thermostat | 13 | |
| 16300512742 | What happens to the resistance of an LDR and the light intensity increases? | Decreases | 14 | |
| 16300512743 | Give a use of LDR's in circuits | Switching lights on | 15 | |
| 16300512744 | What is ohms law? | The law that states that the current flowing through a resistor at constant temperature is directly proportional to the voltage across the resistor | 16 | |
| 16300512745 | Compare Series Circuits vs Parallel Circuits | Series circuit has the same current everywhere, whereas in a parallel circuit the current splits between the branches The potential difference in a series circuit is shared by components, but in parallel circuits, the potential difference is the same everywhere In parallel circuits, the total resistance of 2 resistors is less than the resistance of the smallest individual resistor, but in series circuits, the total resistance is the sum of the resistance of each component equals R1 + R2 | 17 | |
| 16300512746 | What happens to the total resistance of a circuit as you add more light bulbs? (series and parallel) | The resistance decreases | 18 | |
| 16300512747 | Is the main electricity AC or DC? | AC | 19 | |
| 16300512748 | In the UK, what is mains frequency/voltage? | Frequency is 50Hz and Voltage is 230V | 20 | |
| 16300512749 | What does the live wire carry? | Carries the alternating potential difference from the supply | 21 | |
| 16300512750 | What does the neutral wire do? | It completes the circuit | 22 | |
| 16300512751 | What is the earth wire? | Is a safety wire to stop the appliance becoming live | 23 | |
| 16300512752 | What is the colour of the live wire? | Brown | 24 | |
| 16300512753 | What is the colour of the neutral wire? | Blue | 25 | |
| 16300512754 | What is the colour of the earth wire? | Green and Yellow | 26 | |
| 16300512755 | What are the equations for electrical power? | Power (W) = potential difference (V) x Current (A) Power (W)- Current^2(A) x Resistance (Ohms) | 27 | |
| 16300512756 | What is done when charge flows in a circuit? | Work is done | 28 | |
| 16300512757 | What equation links energy transferred, charge flow and potential difference? | Energy transferred (J) = Charge Flow (C) x Potential Difference (V) | 29 | |
| 16300512758 | What is a power rating of an appliance? | It tells us how much electricity an appliance uses | 30 | |
| 16300512759 | What is the national grid? | A system of cables and transformers linking power stations to consumers | 31 | |
| 16300512760 | What are the roles of step up transformers | Used to increase the potential difference cables (reduce energy loss) | 32 | |
| 16300512761 | What are the roles of step down transformers | Used to decrease the potential difference so it is safe for domestic use | 33 | |
| 16300512762 | Why is the national grid system an efficient way to transfer energy? | Step-up transformers produce very high voltages which mean it is easy and quick to transmit electricity, and step-down transformers bring the electricity down to a safe voltage to use. | 34 | |
| 16300512763 | Why does the resistance increase in a filament when the temperature increases? | As it does not follow Ohm's law. | 35 | |
| 16300512803 | Draw the symbol for a battery. |  | 36 | |
| 16300512764 | What is the difference between a battery and a cell? | A cell is just one, but a battery is more than one cell put together | 37 | |
| 16300512804 | Draw the symbol for an ammeter. |  | 38 | |
| 16300512765 | How must an ammeter be placed in a circuit? | Placed in series | 39 | |
| 16300512805 | Draw the symbol for a voltmeter. |  | 40 | |
| 16300512766 | How must a voltmeter be placed in a circuit? | Placed in parallel | 41 | |
| 16300512806 | Draw the symbol for a lamp. |  | 42 | |
| 16300512807 | Draw the symbol for a diode. |  | 43 | |
| 16300512808 | Draw the symbol for a resistor. |  | 44 | |
| 16300512809 | Draw the symbol for a LED (light emitting diodes). |  | 45 | |
| 16300512810 | Draw the symbol for a variable resistor. |  | 46 | |
| 16300512811 | Draw the symbol for a LDR (light dependent resistor). |  | 47 | |
| 16300512812 | Draw the symbol for a fuse. |  | 48 | |
| 16300512813 | Draw the symbol for a thermistor. |  | 49 | |
| 16300512814 | Draw the symbol for an open switch. |  | 50 | |
| 16300512815 | Draw the symbol for a closed switch. |  | 51 | |
| 16300512767 | What is difference between series and parallel circuits? | Just one wire, but parallel has multiple wires and does not go in a square | 52 | |
| 16300512768 | Define charge. | Amount of electricity | 53 | |
| 16300512769 | Define current. | Flow of electrons | 54 | |
| 16300512770 | What is equation taking charge, current and time? | Charge flow= Current x Time |  | 55 |
| 16300512771 | What are the units for charge? | Coulombs | 56 | |
| 16300512772 | What are the units for current? | Amps | 57 | |
| 16300512773 | What are the units for time? | Seconds | 58 | |
| 16300512774 | Define potential difference. | What pushes the current around | 59 | |
| 16300512775 | Define resistance. | What controls the flow | 60 | |
| 16300512776 | What is equation linking potential difference, current and resistance? | Potential Difference = Current x Resistance |  | 61 |
| 16300512777 | What are the units of potential difference? | Volts | 62 | |
| 16300512778 | What are the units for resistance? | Ohms | 63 | |
| 16300512816 | Draw the current-potential different graphs for a conductor. |  | 64 | |
| 16300512817 | Draw the current-potential different graphs for lamp. |  | 65 | |
| 16300512818 | Draw the current-potential different graphs for a diode. |  | 66 | |
| 16300512779 | How does resistance of a thermistor change as temperature changes? | Temperature increase causes resistance decrease |  | 67 |
| 16300512780 | How does resistance of an LDR change as light intensity changes? | Increase in light intensity causes resistance to decrease |  | 68 |
| 16300512781 | How does current behave in a series circuit? | The same throughout | 69 | |
| 16300512782 | How does potential difference behave in a series circuit? | Splits between components | 70 | |
| 16300512783 | How does resistance behave in a series circuit? | Add all resisters together to get total resistance | 71 | |
| 16300512784 | How does current behave in a parallel circuit? | Splits across branches | 72 | |
| 16300512785 | How does potential difference behave in a parallel circuit? | The same throughout | 73 | |
| 16300512786 | Calculate resistance in a parallel circuit | 1/R = 1/R1 + 1/R2 |  | 74 |
| 16300512787 | What is the voltage of mains electricity in the UK? | 230 V | 75 | |
| 16300512788 | What is the frequency of mains electricity in the UK? | 50 Hz | 76 | |
| 16300512789 | What is the difference between alternating and direct current? | Direct current goes in one direction, alternating current goes in difference directions | 77 | |
| 16300512790 | What are the three wires inside a plug? | Live, Neutral and Earth | 78 | |
| 16300512791 | What are the safety features on a plug? | Covered in Plastic, and has a fuse | 79 | |
| 16300512792 | What are the units for power? | Watts | 80 | |
| 16300512793 | What is the equation linking power, current and resistance? | Power= Current^2 x Resistance |  | 81 |
| 16300512794 | What is equation linking energy, power and time? | Energy = Power x Time |  | 82 |
| 16300512795 | What are the units for energy? | J | 83 | |
| 16300512796 | What are the units for time? | Seconds | 84 | |
| 16300512797 | What is equation linking energy, charge and potential difference? | Energy = Charge x Potential Difference |  | 85 |
| 16300512798 | What is the National Grid? | A network of cables that send electricity around the UK | 86 | |
| 16300512799 | What does step up transformer do? | Increase voltage | 87 | |
| 16300512800 | What does a step-down transformer do? | Decrease voltage | 88 | |
| 16300512801 | Use of thermistors | Central heating | 89 | |
| 16300512802 | 2 Uses of LDRS | Street Lights or Security Lights | 90 |