Electricity and Magnetism

Current Electricity - Terminologies used in current electricity

By the end of the lesson, the learner should be able to:
- Define current, potential difference, resistance and electromotive force
- State SI units for electrical quantities
- Connect electrical terms to household appliances like bulbs, heaters and phone chargers

In groups, learners are guided to:
- Use digital devices or reference books to find meanings of electrical terms
- Discuss current, potential difference, e.m.f. and internal resistance
- Identify symbols and units for electrical quantities
- Share findings on terminology in class discussion

How is electromotive force different from potential difference in an electrical circuit?

- Triumph Physics 10 pg. 213
- Digital devices
- Reference books
- Writing materials

- Oral questions - Written assignments - Observation

Electricity and Magnetism

Current Electricity - Terminologies used in current electricity

By the end of the lesson, the learner should be able to:
- Define current, potential difference, resistance and electromotive force
- State SI units for electrical quantities
- Connect electrical terms to household appliances like bulbs, heaters and phone chargers

In groups, learners are guided to:
- Use digital devices or reference books to find meanings of electrical terms
- Discuss current, potential difference, e.m.f. and internal resistance
- Identify symbols and units for electrical quantities
- Share findings on terminology in class discussion

How is electromotive force different from potential difference in an electrical circuit?

- Triumph Physics 10 pg. 213
- Digital devices
- Reference books
- Writing materials

- Oral questions - Written assignments - Observation

Electricity and Magnetism

Current Electricity - Relationship between potential difference and current through a conductor
Current Electricity - Ohm's Law and electrical resistance

By the end of the lesson, the learner should be able to:
- Investigate the relationship between potential difference and current
- Verify Ohm's Law experimentally
- Connect Ohm's Law to understanding why thicker wires carry more current in house wiring
- State Ohm's Law and apply V=IR to solve problems
- Calculate resistance, current or voltage using Ohm's Law
- Connect Ohm's Law to selecting appropriate fuses for electrical appliances

In groups, learners are guided to:
- Set up circuit with nichrome wire, ammeter, voltmeter and variable resistor
- Adjust voltage and record corresponding current readings
- Plot voltage against current graph
- Determine resistance from gradient of graph
- Derive mathematical relationship V=IR from experimental data
- Define the ohm as unit of resistance
- Solve numerical problems using Ohm's Law
- Discuss practical applications of Ohm's Law

What happens to current when potential difference across a conductor is doubled?
Why is it important to know the resistance of a component when designing electrical circuits?

- Triumph Physics 10 pg. 214
- Nichrome wire
- Ammeter
- Voltmeter
- Variable resistor
- Dry cells
- Triumph Physics 10 pg. 216
- Graph paper
- Calculators
- Exercise books

- Practical assessment - Written assignments - Observation
- Written assignments - Oral questions - Observation

Electricity and Magnetism

Current Electricity - Ohm's Law and electrical resistance

By the end of the lesson, the learner should be able to:
- State Ohm's Law and apply V=IR to solve problems
- Calculate resistance, current or voltage using Ohm's Law
- Connect Ohm's Law to selecting appropriate fuses for electrical appliances

In groups, learners are guided to:
- Derive mathematical relationship V=IR from experimental data
- Define the ohm as unit of resistance
- Solve numerical problems using Ohm's Law
- Discuss practical applications of Ohm's Law

Why is it important to know the resistance of a component when designing electrical circuits?

- Triumph Physics 10 pg. 216
- Graph paper
- Calculators
- Exercise books

- Written assignments - Oral questions - Observation

Electricity and Magnetism

Current Electricity - Ohmic and non-ohmic resistors

By the end of the lesson, the learner should be able to:
- Distinguish between ohmic and non-ohmic resistors
- Draw current-voltage graphs for ohmic and non-ohmic conductors
- Connect non-ohmic behaviour to filament bulbs dimming when voltage drops

In groups, learners are guided to:
- Set up circuit with carbon resistor and record current-voltage readings
- Replace with filament bulb and record readings
- Plot I-V graphs for both and compare shapes
- Discuss why filament bulb resistance changes with temperature

Why does a filament bulb's resistance increase as it gets hotter?

- Triumph Physics 10 pg. 217
- Carbon resistor
- Filament bulb
- Ammeter
- Voltmeter
- Dry cells

- Practical assessment - Written assignments - Observation

Electricity and Magnetism

Current Electricity - Effect of length on resistance of conductors

By the end of the lesson, the learner should be able to:
- Investigate how length affects resistance of a conductor
- Establish that resistance is directly proportional to length
- Connect length-resistance relationship to why extension cords have higher resistance

In groups, learners are guided to:
- Set up circuit with nichrome wire mounted on scale
- Measure resistance for different lengths of wire
- Plot resistance against length graph
- Discuss the direct proportionality between length and resistance

Why do longer wires have higher resistance than shorter wires of the same material?

- Triumph Physics 10 pg. 219
- Nichrome wire (100 cm)
- Ammeter
- Voltmeter
- Dry cells

- Practical assessment - Written assignments - Observation

Electricity and Magnetism

Current Electricity - Effect of cross-sectional area on resistance

By the end of the lesson, the learner should be able to:
- Investigate how cross-sectional area affects resistance
- Establish inverse relationship between area and resistance
- Connect area-resistance relationship to thick cables used in power transmission lines

In groups, learners are guided to:
- Set up circuit with nichrome wires of different thicknesses
- Measure resistance for 0.2 mm and 0.4 mm diameter wires
- Compare average resistance values
- Discuss why thicker wires have lower resistance

Why are thick copper cables used for transmitting electricity over long distances?

- Triumph Physics 10 pg. 221
- Nichrome wires of different diameters
- Ammeter
- Voltmeter
- Dry cells

- Practical assessment - Written assignments - Observation

Electricity and Magnetism

Current Electricity - Effect of cross-sectional area on resistance

By the end of the lesson, the learner should be able to:
- Investigate how cross-sectional area affects resistance
- Establish inverse relationship between area and resistance
- Connect area-resistance relationship to thick cables used in power transmission lines

In groups, learners are guided to:
- Set up circuit with nichrome wires of different thicknesses
- Measure resistance for 0.2 mm and 0.4 mm diameter wires
- Compare average resistance values
- Discuss why thicker wires have lower resistance

Why are thick copper cables used for transmitting electricity over long distances?

- Triumph Physics 10 pg. 221
- Nichrome wires of different diameters
- Ammeter
- Voltmeter
- Dry cells

- Practical assessment - Written assignments - Observation

Electricity and Magnetism

Current Electricity - Effect of cross-sectional area on resistance
Current Electricity - Effect of material type and temperature on resistance

By the end of the lesson, the learner should be able to:
- Investigate how cross-sectional area affects resistance
- Establish inverse relationship between area and resistance
- Connect area-resistance relationship to thick cables used in power transmission lines
- Investigate how material type and temperature affect resistance
- Define and use resistivity in calculations
- Connect material properties to why copper is preferred for electrical wiring over nichrome

In groups, learners are guided to:
- Set up circuit with nichrome wires of different thicknesses
- Measure resistance for 0.2 mm and 0.4 mm diameter wires
- Compare average resistance values
- Discuss why thicker wires have lower resistance
- Compare resistance of nichrome and copper wires of same dimensions
- Heat nichrome wire and measure resistance change
- Discuss resistivity values of different materials
- Calculate resistance using R = ρl/A

Why are thick copper cables used for transmitting electricity over long distances?
Why does the resistance of metals increase when they are heated?

- Triumph Physics 10 pg. 221
- Nichrome wires of different diameters
- Ammeter
- Voltmeter
- Dry cells
- Triumph Physics 10 pg. 222
- Nichrome and copper wires
- Hot water
- Ammeter
- Voltmeter

- Practical assessment - Written assignments - Observation
- Practical assessment - Written assignments - Oral questions

Electricity and Magnetism

Current Electricity - Relationship between e.m.f., voltage, current, resistance and internal resistance

By the end of the lesson, the learner should be able to:
- Derive and apply the equation E = I(R + r)
- Calculate internal resistance and terminal voltage
- Connect internal resistance to why car batteries struggle to start engines in cold weather

In groups, learners are guided to:
- Set up circuit with cell, ammeter, voltmeter and variable resistor
- Record voltage and current for different resistance values
- Plot V against I graph and determine e.m.f. and internal resistance
- Solve problems using E = I(R + r)

Why is the terminal voltage of a battery always less than its e.m.f. when current flows?

- Triumph Physics 10 pg. 225
- Dry cell
- Ammeter
- Voltmeter
- Variable resistor

- Practical assessment - Written assignments - Observation

Electricity and Magnetism

Current Electricity - Types of resistors and resistor networks

By the end of the lesson, the learner should be able to:
- Identify fixed and variable resistors and state their uses
- Draw symbols for different types of resistors
- Connect resistor types to volume controls in radios and dimmer switches in homes

In groups, learners are guided to:
- Identify fixed resistors (carbon) and variable resistors (rheostat, potentiometer, thermistor)
- Draw circuit symbols for each resistor type
- Discuss uses of each type of resistor
- Complete table showing resistor types, symbols and uses

How do variable resistors help control the brightness of lights and volume of sound?

- Triumph Physics 10 pg. 227
- Various resistors
- Circuit symbol charts
- Exercise books

- Oral questions - Written assignments - Observation

Electricity and Magnetism

Current Electricity - Types of resistors and resistor networks

By the end of the lesson, the learner should be able to:
- Identify fixed and variable resistors and state their uses
- Draw symbols for different types of resistors
- Connect resistor types to volume controls in radios and dimmer switches in homes

In groups, learners are guided to:
- Identify fixed resistors (carbon) and variable resistors (rheostat, potentiometer, thermistor)
- Draw circuit symbols for each resistor type
- Discuss uses of each type of resistor
- Complete table showing resistor types, symbols and uses

How do variable resistors help control the brightness of lights and volume of sound?

- Triumph Physics 10 pg. 227
- Various resistors
- Circuit symbol charts
- Exercise books

- Oral questions - Written assignments - Observation

Electricity and Magnetism

Current Electricity - Measurement of resistance using resistor colour codes

By the end of the lesson, the learner should be able to:
- Read resistance values from colour coded resistors
- Calculate resistance and tolerance from colour bands
- Connect colour coding to identifying resistor values when repairing electronic devices

In groups, learners are guided to:
- Study resistor colour code chart
- Observe colour bands on fixed carbon resistors
- Calculate resistance values using colour codes
- Verify calculated values using digital multimeter

How do the colour bands on a resistor indicate its resistance value and tolerance?

- Triumph Physics 10 pg. 228
- Fixed carbon resistors
- Colour code chart
- Digital multimeter

- Practical assessment - Written assignments - Observation

Electricity and Magnetism

Current Electricity - Measurement of resistance using resistor colour codes

By the end of the lesson, the learner should be able to:
- Read resistance values from colour coded resistors
- Calculate resistance and tolerance from colour bands
- Connect colour coding to identifying resistor values when repairing electronic devices

In groups, learners are guided to:
- Study resistor colour code chart
- Observe colour bands on fixed carbon resistors
- Calculate resistance values using colour codes
- Verify calculated values using digital multimeter

How do the colour bands on a resistor indicate its resistance value and tolerance?

- Triumph Physics 10 pg. 228
- Fixed carbon resistors
- Colour code chart
- Digital multimeter

- Practical assessment - Written assignments - Observation

Electricity and Magnetism

Current Electricity - Measurement of resistance using ammeter-voltmeter and Wheatstone bridge

By the end of the lesson, the learner should be able to:
- Measure resistance using ammeter-voltmeter method
- Explain the working principle of Wheatstone bridge
- Connect Wheatstone bridge to precision measurements in laboratory instruments

In groups, learners are guided to:
- Set up circuit to measure resistance using ammeter-voltmeter method
- Calculate resistance using R = V/I
- Set up Wheatstone bridge and balance it for zero deflection
- Calculate unknown resistance using bridge formula

Why is the Wheatstone bridge more accurate than the ammeter-voltmeter method?

- Triumph Physics 10 pg. 231
- Ammeter
- Voltmeter
- Wheatstone bridge
- Galvanometer

- Practical assessment - Written assignments - Observation

Electricity and Magnetism

Current Electricity - Measurement of resistance using ammeter-voltmeter and Wheatstone bridge

By the end of the lesson, the learner should be able to:
- Measure resistance using ammeter-voltmeter method
- Explain the working principle of Wheatstone bridge
- Connect Wheatstone bridge to precision measurements in laboratory instruments

In groups, learners are guided to:
- Set up circuit to measure resistance using ammeter-voltmeter method
- Calculate resistance using R = V/I
- Set up Wheatstone bridge and balance it for zero deflection
- Calculate unknown resistance using bridge formula

Why is the Wheatstone bridge more accurate than the ammeter-voltmeter method?

- Triumph Physics 10 pg. 231
- Ammeter
- Voltmeter
- Wheatstone bridge
- Galvanometer

- Practical assessment - Written assignments - Observation

Electricity and Magnetism

Current Electricity - Measurement of resistance using ammeter-voltmeter and Wheatstone bridge

By the end of the lesson, the learner should be able to:
- Measure resistance using ammeter-voltmeter method
- Explain the working principle of Wheatstone bridge
- Connect Wheatstone bridge to precision measurements in laboratory instruments

In groups, learners are guided to:
- Set up circuit to measure resistance using ammeter-voltmeter method
- Calculate resistance using R = V/I
- Set up Wheatstone bridge and balance it for zero deflection
- Calculate unknown resistance using bridge formula

Why is the Wheatstone bridge more accurate than the ammeter-voltmeter method?

- Triumph Physics 10 pg. 231
- Ammeter
- Voltmeter
- Wheatstone bridge
- Galvanometer

- Practical assessment - Written assignments - Observation

Electricity and Magnetism

Current Electricity - Measurement of resistance using metre bridge

By the end of the lesson, the learner should be able to:
- Describe the metre bridge as a practical form of Wheatstone bridge
- Use metre bridge to determine unknown resistance
- Connect metre bridge principle to strain gauges used in weighing scales

In groups, learners are guided to:
- Set up metre bridge circuit with known and unknown resistors
- Slide jockey along wire until galvanometer shows zero deflection
- Record balance lengths and calculate unknown resistance
- Compare calculated values with standard values

How does the metre bridge use the principle of balanced ratios to measure resistance?

- Triumph Physics 10 pg. 233
- Metre bridge
- Known resistor
- Unknown resistor
- Galvanometer

- Practical assessment - Written assignments - Observation

Electricity and Magnetism

Current Electricity - Effective resistance of resistors in series

By the end of the lesson, the learner should be able to:
- Derive formula for effective resistance of resistors in series
- Calculate total resistance and voltage drops in series circuits
- Connect series circuits to Christmas lights where one faulty bulb affects all others

In groups, learners are guided to:
- Connect resistors in series with ammeter and voltmeters
- Measure total voltage and individual voltage drops
- Verify that R_total = R₁ + R₂ + R₃
- Solve numerical problems on series resistor networks

Why does adding more resistors in series increase the total resistance of a circuit?

- Triumph Physics 10 pg. 234
- Resistors
- Ammeter
- Voltmeters
- Dry cells

- Practical assessment - Written assignments - Observation

Electricity and Magnetism

Current Electricity - Effective resistance of resistors in series

By the end of the lesson, the learner should be able to:
- Derive formula for effective resistance of resistors in series
- Calculate total resistance and voltage drops in series circuits
- Connect series circuits to Christmas lights where one faulty bulb affects all others

In groups, learners are guided to:
- Connect resistors in series with ammeter and voltmeters
- Measure total voltage and individual voltage drops
- Verify that R_total = R₁ + R₂ + R₃
- Solve numerical problems on series resistor networks

Why does adding more resistors in series increase the total resistance of a circuit?

- Triumph Physics 10 pg. 234
- Resistors
- Ammeter
- Voltmeters
- Dry cells

- Practical assessment - Written assignments - Observation

Electricity and Magnetism

Current Electricity - Effective resistance of resistors in series

By the end of the lesson, the learner should be able to:
- Derive formula for effective resistance of resistors in series
- Calculate total resistance and voltage drops in series circuits
- Connect series circuits to Christmas lights where one faulty bulb affects all others

In groups, learners are guided to:
- Connect resistors in series with ammeter and voltmeters
- Measure total voltage and individual voltage drops
- Verify that R_total = R₁ + R₂ + R₃
- Solve numerical problems on series resistor networks

Why does adding more resistors in series increase the total resistance of a circuit?

- Triumph Physics 10 pg. 234
- Resistors
- Ammeter
- Voltmeters
- Dry cells

- Practical assessment - Written assignments - Observation

Electricity and Magnetism

Current Electricity - Effective resistance of resistors in series

By the end of the lesson, the learner should be able to:
- Derive formula for effective resistance of resistors in series
- Calculate total resistance and voltage drops in series circuits
- Connect series circuits to Christmas lights where one faulty bulb affects all others

In groups, learners are guided to:
- Connect resistors in series with ammeter and voltmeters
- Measure total voltage and individual voltage drops
- Verify that R_total = R₁ + R₂ + R₃
- Solve numerical problems on series resistor networks

Why does adding more resistors in series increase the total resistance of a circuit?

- Triumph Physics 10 pg. 234
- Resistors
- Ammeter
- Voltmeters
- Dry cells

- Practical assessment - Written assignments - Observation

Electricity and Magnetism

Current Electricity - Effective resistance of resistors in parallel

By the end of the lesson, the learner should be able to:
- Derive formula for effective resistance of resistors in parallel
- Calculate total resistance and branch currents in parallel circuits
- Connect parallel circuits to house wiring where each appliance operates independently

In groups, learners are guided to:
- Connect resistors in parallel with ammeter and voltmeters
- Measure total current and individual branch currents
- Verify that 1/R_total = 1/R₁ + 1/R₂ + 1/R₃
- Solve numerical problems on parallel resistor networks

Why is the total resistance of parallel resistors always less than the smallest individual resistor?

- Triumph Physics 10 pg. 237
- Resistors
- Ammeter
- Voltmeters
- Dry cells

- Practical assessment - Written assignments - Observation

Electricity and Magnetism

Current Electricity - Effective resistance of resistors in parallel

By the end of the lesson, the learner should be able to:
- Derive formula for effective resistance of resistors in parallel
- Calculate total resistance and branch currents in parallel circuits
- Connect parallel circuits to house wiring where each appliance operates independently

In groups, learners are guided to:
- Connect resistors in parallel with ammeter and voltmeters
- Measure total current and individual branch currents
- Verify that 1/R_total = 1/R₁ + 1/R₂ + 1/R₃
- Solve numerical problems on parallel resistor networks

Why is the total resistance of parallel resistors always less than the smallest individual resistor?

- Triumph Physics 10 pg. 237
- Resistors
- Ammeter
- Voltmeters
- Dry cells

- Practical assessment - Written assignments - Observation

Electricity and Magnetism

Current Electricity - Effective resistance of resistors in parallel

By the end of the lesson, the learner should be able to:
- Derive formula for effective resistance of resistors in parallel
- Calculate total resistance and branch currents in parallel circuits
- Connect parallel circuits to house wiring where each appliance operates independently

In groups, learners are guided to:
- Connect resistors in parallel with ammeter and voltmeters
- Measure total current and individual branch currents
- Verify that 1/R_total = 1/R₁ + 1/R₂ + 1/R₃
- Solve numerical problems on parallel resistor networks

Why is the total resistance of parallel resistors always less than the smallest individual resistor?

- Triumph Physics 10 pg. 237
- Resistors
- Ammeter
- Voltmeters
- Dry cells

- Practical assessment - Written assignments - Observation

Electricity and Magnetism

Current Electricity - Relationship between voltage, current and power in heating effect

By the end of the lesson, the learner should be able to:
- Derive and apply P = VI, P = I²R and H = I²Rt
- Calculate electrical power and energy consumed
- Connect heating effect to electric kettles, heaters and toasters in homes

In groups, learners are guided to:
- Set up circuit with resistor, ammeter and voltmeter
- Record voltage and current at different settings
- Calculate power using P = VI
- Derive Joule's law of electrical heating H = I²Rt

How does the resistance of a heating element affect the amount of heat produced?

- Triumph Physics 10 pg. 241
- Resistor
- Ammeter
- Voltmeter
- Rheostat

- Written assignments - Oral questions - Observation

Electricity and Magnetism

Current Electricity - Applications of the heating effect of electric current

By the end of the lesson, the learner should be able to:
- Describe applications of electrical heating in various devices
- Explain the role of fuses in circuit protection
- Connect heating applications to cooking appliances, lighting and industrial furnaces

In groups, learners are guided to:
- Research applications of heating effect in cooking appliances, lighting and circuit protection
- Discuss how fuses and circuit breakers protect circuits
- Compare ohmic devices (heaters) and non-ohmic devices (filament bulbs)
- Present findings on applications to class

How do fuses use the heating effect of current to protect electrical circuits?

- Triumph Physics 10 pg. 245
- Digital devices
- Reference books
- Various electrical appliances

- Written assignments - Oral questions - Observation

Electricity and Magnetism

Current Electricity - Applications of the heating effect of electric current

By the end of the lesson, the learner should be able to:
- Describe applications of electrical heating in various devices
- Explain the role of fuses in circuit protection
- Connect heating applications to cooking appliances, lighting and industrial furnaces

In groups, learners are guided to:
- Research applications of heating effect in cooking appliances, lighting and circuit protection
- Discuss how fuses and circuit breakers protect circuits
- Compare ohmic devices (heaters) and non-ohmic devices (filament bulbs)
- Present findings on applications to class

How do fuses use the heating effect of current to protect electrical circuits?

- Triumph Physics 10 pg. 245
- Digital devices
- Reference books
- Various electrical appliances

- Written assignments - Oral questions - Observation

Electricity and Magnetism

Current Electricity - Applications of the heating effect of electric current

By the end of the lesson, the learner should be able to:
- Describe applications of electrical heating in various devices
- Explain the role of fuses in circuit protection
- Connect heating applications to cooking appliances, lighting and industrial furnaces

In groups, learners are guided to:
- Research applications of heating effect in cooking appliances, lighting and circuit protection
- Discuss how fuses and circuit breakers protect circuits
- Compare ohmic devices (heaters) and non-ohmic devices (filament bulbs)
- Present findings on applications to class

How do fuses use the heating effect of current to protect electrical circuits?

- Triumph Physics 10 pg. 245
- Digital devices
- Reference books
- Various electrical appliances

- Written assignments - Oral questions - Observation

Electricity and Magnetism

Current Electricity - Applications of the heating effect of electric current

By the end of the lesson, the learner should be able to:
- Describe applications of electrical heating in various devices
- Explain the role of fuses in circuit protection
- Connect heating applications to cooking appliances, lighting and industrial furnaces

In groups, learners are guided to:
- Research applications of heating effect in cooking appliances, lighting and circuit protection
- Discuss how fuses and circuit breakers protect circuits
- Compare ohmic devices (heaters) and non-ohmic devices (filament bulbs)
- Present findings on applications to class

How do fuses use the heating effect of current to protect electrical circuits?

- Triumph Physics 10 pg. 245
- Digital devices
- Reference books
- Various electrical appliances

- Written assignments - Oral questions - Observation