Transcript The ‘coulomb per volt’ is a unit of

St Columba’s High School
Electricity and Electronics
Capacitors
The ‘coulomb per volt’ is a unit of
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Charge
Energy
Capacitance
Potential difference
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Capacitors store
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Current
Charge
Voltage
Power
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Capacitors
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1. Block a.c. but pass d.c
2. Block d.c and a.c.
3. Block d.c. but pass a.c.
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An 8 μF capacitor requires
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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 ?
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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
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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 :
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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
2. B
3. C
B
4. D
C
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D
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B
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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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1. Remain constant
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2. Decrease steadily
3. Increase then decrease
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4. Increase steadily
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The maximum value of the current
flowing is :
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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 ?
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Increases
2. Stays the same
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3. 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
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