S3 PHYSICS ELECTIVEElectricity Pupil Booklet
Duncanrig Secondary School
East Kilbride
S3 Physics Elective
Electricity
Pupil Booklet
- Learning Outcomes
- Homework
- Summary
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S3 PHYSICS ELECTIVEElectricity Pupil Booklet
How Confident am I with the Content Statements?
- Circle the symbols to keep a record of your progress.
I am confident that I understand this and I can apply this to problems
I have some understanding but I need to revise this some more
I don’t know this or I need help because I don’t understand it
- You can use this to help you pick the areas of the unit that need the most revision.
- As you revise your class work you will be able to circle more and more smiley faces.
- If that does not help then you should ask your teacher!
Learning Outcomes / Can you do this? / Comments
Circuits
- Draw and identify the circuit symbol for a single cell, battery, wire, fuse, lamp, switch, resistor, variable resistor, voltmeter, ammeter and ohmmeter.
- State that a single cell or battery is a source of electrical energy.
Electric Current and Ammeters
- State that current is a flow of charges around a circuit and is measured in amperes
- State that the current in a circuit is a measure of the charges per second through a conductor.
- State that an ammeter measures electric current.
- State that an ammeter is connected in series with a component.
- State that the unit of electric current is the ampere, abbreviation A.
- Use correctly the unit: ampere, A.
- Draw circuit diagrams to show the correct position of an ammeter in a circuit.
- State that a good ammeter has a very low resistance.
- State that the current in a series circuit is the same at each point in the circuit.
- State that in a parallel circuit, the sum of the current in each of the branches is equal to the supply current.
Voltage and Voltmeters
- State that the voltage of a supply is a measure of the energy given to the charges flowing round a circuit.
- State that a voltmeter measures voltage.
- State that a voltmeter is connected in parallel with a component.
- State that the unit of voltage is the volt, abbreviation, V.
- Use correctly the unit: volt, V.
- Draw circuit diagrams to show the correct position of a voltmeter in a circuit.
- State that a good voltmeter has a very high resistance.
- State that in a series circuit, the sum of the voltage across each component in a circuit is equal to the supply voltage.
- State that in a parallel circuit, the voltage in each branch is equal to the supply voltage.
Resistance and Ohm’s Law
- State that resistors convert electrical energy into heat energy.
- State that an ohmmeter is used to measure resistance.
- State that resistance is measured in ohms, abbreviation Ω.
- State that an increase in resistance of a circuit leads to a decrease in the current in the circuit.
- Calculate the resistance in ohms of a component using Ohm’s Law:
- State how the value of the resistance of a lamp changes with current.
- State that when there is an electric current in a wire, there is an energy transformation.
- Carry out calculations involving the relationship between resistance, current and voltage.
- Use correctly the unit: ohm (Ω)
- State that a short connecting wire has a resistance of approximately 0.3 Ω, a torch bulb 15 Ω and a heater ring 1000 Ω.
- State that V/I for a resistor remains approximately constant for different currents.
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S3 PHYSICS ELECTIVEElectricity Pupil Booklet
Elective Homework – Getting Started
Success involves doing many kinds of problems which help improve your knowledge and understanding of the ideas in the course and your ability to solve problems. To get started we will look at a general method for tackling problems.
General Method for Solving Problems.
Any numerical problem in Physics can be solved using the following steps:
- Read the question carefully.
- Find out exactly what is being asked.
- Extract the key data.
- Select the correct equation.
- Substitute the data into the equation and find the missing variable.
- Give the answer and correct unit.
Example
How far does a cyclist travel in 26 seconds if she is travelling at a constant speed of 8 metres per second?
Solution
Read the question carefully
Find out exactly what is being asked Distance (how far)
Extract the key data time = 26 seconds
speed = 8 metres per second
Select the correct equation distance = speed x time
Substitute data into equation d = 8 x 26
Give the answer and correct unit d = 208 m
Usual Layout
d = ?v = 8 m/s
t = 26 s / d = v x t
= 8 x 26
= 208 m
All numerical questions in the following homework exercises should be carried out in this way. No marks will be awarded for an answer given without the working being shown.
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S3 PHYSICS ELECTIVEElectricity Pupil Booklet
Homework 1CIRCUITS
- Unjumble the letters to name some frequently used components in electric circuits. You will find help on page 16 of this booklet.
- EUSF6. MEERTAM
- PALM7. TISESROR
- RETTYAB8. MRHOEMET
- GLESIN ECLL9. OTEEMTLVR
- REIW10. TIWSHC(5)
- Which two of the components above provide a source of electrical energy? (2)
- Draw a series circuit showing a battery, lamp, fuse and
a variable resistor all connected up so that the bulb would light.
Use a ruler to draw your components.(2)
- Batteries provide electrical energy to make our portable
appliances work.
Suggest another two sources of electrical energy.(2)
TOTAL [11]
PUT YOUR ANSWERS TO HOMEWORK 1 CIRCUITS HERE
Homework 2ELECTRIC CURRENT AND AMMETERS
You will find help on page 17 of this booklet.
- What is meant by an electric current?
In which units is electric current measured?(2)
- In the circuit shown below, the current reading on one of the
ammeters is 0.2 amperes.
State the current reading on the other ammeter and the current
through each lamp.(2)
- Small currents are measured in milliamperes mA.
1 mA = 1/1000 A = 0.001 A and1000 mA = 1 A
Rewrite the following electric currents in increasing order (smallest first)
5.3 A, 5.3 mA, 3.5 A, 750 mA, 0.5 A, 250 mA, 3.5 mA,(1)
- What will be the readings on A2 and A3 if A1 reads 0.65 A and A4 reads
0.2 A?(2)
TOTAL [7]
PUT YOUR ANSWERS TO
HOMEWORK2 ELECTRIC CURRENT AND AMMETERS HERE
Homework 3VOLTAGE AND VOLTMETERS
You will find help on page 18 of this booklet.
- Copy and complete this electrical statement:
The ______of a supply is a measure of the ______
given to the ______flowing round a ______.(2)
- In the circuit below, all the lamps are identical.
(a)Describe how the each voltmeter is connected in the circuit.(1)
(b)Voltmeter V1reads 30 V. What will be the readings on voltmeters V2, V3, V4, V5 and V6? (1)
- Small voltages are measured in millivolts mV.
1 mV = 1/1000 V = 0.001 V and1000 mV = 1 V
Rewrite the following voltages in decreasing order (largest first)
4.0 V, 4 mV, 230 V, 90 mV, 12 V, 120 mV, 60 V, 6 mV, 1.5 V(1)
- Draw a series circuit diagram showing a cell, switch, lamp and fuse with a voltmeter placed correctly measuring the voltage across the cell. (2)
TOTAL [7]
PUT YOUR ANSWERS TO HOMEWORK3 VOLTAGE AND VOLTMETERS HERE
Homework 4RESISTANCE AND OHM’S LAW
You will find help on pages 19 and 20 of this booklet.
- State the energy change in a resistor.(1)
- Name the device used to measure electrical resistance directly.(1)
- What happens to the current in a circuit when the resistance is increased? (1)
- State Ohm’s Law in words and then write down the relationship using symbols. (2)
- What is the voltage across a 12 Ω resistor when there is a 0.45 A current through it? Use Ohm's law to calculate the answer. (3)
- A lamp has a resistance of 920 Ω. It needs to draw a current of 0.25 A to operate at its correct brightness.
What value of voltage does it require?(3)
- The current flowing through a heater is 0.5 A and the voltage across is 6V. What is the value of its resistance? (3)
- A 220 Ω resistor is connected across a 2 volt supply.
Calculate the current in the resistor.(3)
TOTAL [17]
PUT YOUR ANSWERS TO
HOMEWORK4 RESISTANCE AND OHM’S LAW HERE
ELECTRICITY SUMMARY
CIRCUITS
ELECTRICITY SUMMARY
ELECTRIC CURRENT AND AMMETERS
ELECTRICITY SUMMARY
VOLTAGE AND VOLTMETERS
ELECTRICITY SUMMARY
RESISTANCE AND OHM’S LAW
ELECTRICITY SUMMARY
RESISTANCE AND OHM’S LAW
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