Question 1
Question
True or false? In alternating current, the potential difference switches between positive and negative values.
Question 2
Question
Which of these statements are true about the UK mains supply?
Question 3
Question
True or false? The device used to show how alternating potential difference varies with time is called a voltascope.
Question 4
Question
What is the peak voltage of an AC supply whose peak is 3.4cm from the centre and whose Y-gain control is 0.75V/cm?
Question 5
Question
What is the frequency of an AC supply if the length of one cycle is 4cm and the time-base control is 15ms/cm?
Answer
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60Hz
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0.06Hz
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16.67Hz
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0.02Hz
Question 6
Question
What colour cable is the live wire in a three-core cable?
Answer
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Green and yellow
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Brown
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Blue
Question 7
Question
What colour cable is the neutral wire in a three-core cable?
Answer
-
Green and yellow
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Brown
-
Blue
Question 8
Question
What colour cable is the earth wire in a three-core cable?
Answer
-
Green and yellow
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Brown
-
Blue
Question 9
Question
True or false? Appliances with plastic cases such as hairdryers only need two-core cable as they are doubly-insulated and do not need to be earthed.
Question 10
Question
True or false? A circuit breaker is a piece of metal that melts if the current flowing through it is too large.
Question 11
Question
What fuse would you need to buy if an appliance drew 2.7A of current?
Question 12
Question
True or false? Residual current circuit breakers break if the current in the live wire is different to the current in the neutral wire.
Question 13
Question
Which of these equations connecting power, energy and time is correct?
Question 14
Question
Which of these equations connecting power, current and potential difference is correct?
Question 15
Question
What fuse would I buy if I bought a 230V, 1000W appliance?
Question 16
Question
How many units of charge would each electron carry if they carried 6A of current in 1 minute?
Question 17
Question
True or false? The equation connecting charge, potential difference and energy is Q = VE.
Question 18
Question
What would be the potential difference of circuit in which 2000J of energy were carried by electrons with a charge of 4C?
Question 19
Question
True or false? Connecting too many appliances to a single socket can lead to overheating.
Question 20
Question
Which of these are considered energy-efficient bulbs?