Transcript The ‘coulomb per volt’ is a unit of
St Columba’s High School Electricity and Electronics
Capacitors
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The ‘coulomb per volt’ is a unit of 1.
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Charge Energy Capacitance Potential difference
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Capacitors store 1.
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Current Charge Voltage Power
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Capacitors 1.
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Block a.c. but pass d.c
Block d.c and a.c.
Block d.c. but pass a.c.
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An 8 μF capacitor requires 1.
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1 μ C to charge it to 1 V 8 μC to charge it to 8 V 8 μC to charge it to 1 V 8 C to charge it to 8 μV
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What does the shaded area under the graph represent ?
The capacitance of the capacitor The working voltage of the capacitor The charge stored on the plates of the capacitor The energy stored in the capacitor
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What is represented by the gradient of the graph shown ?
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The energy stored by the capacitor The capacitance of the capacitor The charge stored The Current flowing
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A 500 μF capacitor has a potential difference of 20 V across it. The charge stored is 1.
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10 μC 10 mC 50 mC 0.04 μC
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The energy stored in a 500 μF capacitor charged to a voltage of 20 V is : 1.
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0.005 J 0.05 J 0.01J
0.1 J
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A resistor,R, and a capacitor ,C are connected in series.Which graphs are correct for the capacitor charging up ?
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A A 2.
B 3.
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C D B C D
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As the frequency of the supply is increased from 50 to 5000 Hz the reading on the ammeter will :
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Remain constant Decrease steadily Increase then decrease Increase steadily
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The maximum value of the current flowing is :
0 A 0.5 mA 0.5 A 0.005 mA
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If the resistance is increased what happens to the time it takes for the capacitor to charge ?
Increases Stays the same Decreases
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A 25 μF capacitor is charged until the pd across it is 500 V. Calculate the charge stored
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5.00 x 10 -8 C 2.00 x 10 -5 C 1.25 x10 -2 C 1.25 x 10 -4 C
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Calculate the energy stored when the pd across the capacitor is 10 V.
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0.4 mJ 2.5 mJ 10 mJ 20 mJ
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Which answer describes what happens to the bulbs as the frequency is increased but the output voltage remains constant ?
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P brighter Q unchanged P unchanged P dimmer P unchanged Q brighter Q unchanged Q dimmer
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