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INTERMEDIATE 1 PHYSICS
PRACTICAL ELECTRICITY
Homework Booklet
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Teacher:
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Class:
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Electric Components
Copy and complete the following table
Component
Circuit Symbol
Battery
10
Description
Supplies electrical energy.
Converts electrical energy to light
Open: breaks a circuit. Closed: completes a
Switch
circuit.
Heater
Converts electrical energy into heat energy.
Opposes current, it converts electrical energy
Resistor
into heat energy.
Variable
A resistor whose resistance can be changed.
resistor
Motor
Converts electrical energy into kinetic energy.
A
Voltmeter
Ohmmeter
Fuse
Used to measure electric current -always
connected in series.
Used to measure voltage - always connected in
parallel.
Measures resistance directly - use when
component is not connected.
A protection device. It melts when the current
gets too high.
Total = 10 marks
Basic Electricity
1. What do we use to measure voltage in a circuit?
2
2. What is the rule for voltage in a circuit
1
3. Draw a circuit diagram showing a bulb and battery in series. Put a
voltmeter in the diagram to show how you would measure the voltage
across the bulb
2
4. What is the energy change in a resistor?
1
5. What piece of equipment is used to measure resistance?
1
6. What happens to the current in a circuit when resistance increases? 1
7. If a circuit has a voltage of 30V and a current of 5A, what is its
resistance?
2
8. Give two uses for a variable resistor.
1
9. Name the three pins in a plug and the colour of the insulation on the
wires connected to them.
1
Total = 10 marks
Electric Circuits
1. A student collects a lamp, two voltmeters, a battery and some wires
from her science teacher. She connected them as shown in the diagram
below.
a. Has the student set up a series or parallel circuit?
1
b. She notices that lamp B is brighter than lamp A - what does this
tell you about the power of the lamps B compared with lamp A? 2
c. The voltmeter connected across lamp A gives a reading of 2.0
volts. What is the reading on the other voltmeter?
2
d. The student used an ammeter to measure the current in lamp A.
Was the ammeter connected in series or in parallel with the lamp
when measuring the current?
1
e. The ammeter indicates a current of 0.5 amperes flowing through
lamp A. What is the current flowing through lamp B?
f. Calculate the resistance of lamp A.
2
2
Total = 10 marks
Resistance
1. A variable resistor is used in the speed controller of a toy electric
train. The variable resistor controls the current flowing to a small
electric motor in the train shown in figure 1
a. Copy the diagram and complete it by adding a variable resistor. 1
b. At one particular speed the voltage across the variable resistor is
6.0 volts and the current flowing through it is 0.3 amperes.
i. Calculate the resistance of the variable resistor
2
ii. What is the current flowing through in the motor?
2
c. The resistance of the variable resistor in the speed control is now
decreased
i. What will happen to the current following in the motor?
2
ii. What effect will this have on the speed of the toy train? 1
d. Give two other uses of a variable resistor
2
Total = 10 marks
Mains Electricity
1. On a cold morning Peter made some toast for his breakfast.
a. What is the main energy conversion for these appliances?
1
b. Explain why is it dangerous to connect all these appliances to one
socket?
2
c. Draw a simple diagram of the inside of a plug
3
i. Label the fuse
ii. Label the colour of the wires
iii. Name each of the wires
d. There is a fuse in a plug – draw the symbol for a fuse
2
e. The toaster runs off mains voltage (230 volts) and has a power
rating of 1380 Watts – calculate the current running through the
toaster
2
Total = 10 marks
Revision Questions
1.
What type of circuit is connected to allow only one path for current?
2.
What type of circuit is connected to allow more than one path for
current?
3.
What instrument is used to measure the Current in a circuit?
4.
What unit is Current measured in?
5.
What instrument is used to measure the Voltage dropped across
components in a circuit?
6.
What unit is Voltage measured in?
7.
What can be said about the Current at any point in a series circuit?
8.
How does the Voltage dropped across each of the components in a
series circuit compare with the Supply Voltage?
9.
How does the Current through each of the components in a parallel
circuit compare with the Supply Current?
10.
How does the Voltage dropped across each of the components in a
parallel circuit compare with the Supply Voltage?
11.
What name is given to the opposition to Current?
12.
What type of energy does electrical energy convert into in a resistor?
13.
List two electrical appliances that convert Electrical Energy into Heat
Energy.
14.
What unit is Resistance measured in?
15.
What instrument is used to measure Resistance?
16.
State the equation involving Resistance, Current and Voltage?
17.
Calculate the resistance of a resistor if a voltage is 6V dropped across
it and a current of 0.2A is passing through it?
18.
When the Resistance is increased in a circuit then what happens to the
Current?
19.
State the value of the mains voltage in the UK?
20.
State the name of the three terminals in a plug and what colour does
each of these wires have?
21.
What does the symbol for a double insulated appliance look like and
what two wires does this type of appliance contain?
22.
What component is used inside a plug to protect the cable?
23.
What are the two standard sizes of fuse used inside a plug?
24.
State the equation involving Power, Current and Voltage?
25.
Calculate the Current and then the fuse value required for a hairdryer
of power 850W when connected to the mains?
26.
What is the general rule on whether a plug will require a 3A or a 13A
fuse?
27.
How are all circuits connected in a house?
28.
What device is used to protect household circuits in modern houses?
29.
What three components are used in a basic continuity tester?
30.
A multimeter is set to measure resistance and its leads are placed
across a bulb in a circuit. If the reading on the display is 1___
(Infinity), then what type of fault has been detected?