Electricity and Magnetism — Free IB MYP4 Physics Questions

1QuestionMagnetic Field Around a Bar MagnetConcept Practice

2 marks~3 minCriterion A

A hiker uses a magnetic compass to navigate through a forest. The compass needle is a small, freely pivoting bar magnet. The Earth's magnetic field behaves like that of a giant bar magnet, with its magnetic south pole located near geographic north.

a

Explain how the Earth's magnetic field causes the compass needle to point toward geographic north. [1]

b

The hiker enters a valley containing large iron ore deposits. Explain how this affects the reliability of the compass for navigation. [1]

Solutions

2QuestionRight-Hand Rule and Magnetic Direction - AC GeneratorConcept Practice

2 marks~3 minCriterion D

AC generators convert mechanical energy into electrical energy through electromagnetic induction and are used across many real-world contexts.

Discuss one real-world application of an AC generator. In your response, identify one societal benefit and one limitation associated with this application. [2]

Solutions

3QuestionUses of Electromagnets in Real LifeConcept Practice

3 marks~5 minCriterion C

A circuit breaker protects a house from damage caused by a current surge. In a short paragraph, use the terms 'electromagnet', 'spring', and 'trip switch' to explain the sequence of events that happens when a current surge occurs. Also, draw and label a simple diagram of a circuit breaker showing the electromagnet, spring, and trip switch. Explain how each part contributes to the safety function.

Solutions

4QuestionHousehold Wiring and Power RatingsConcept Practice

2 marks~3 minCriterion A

A household circuit contains a 5 A fuse connected to a 240 V kettle rated at 2000 W. A short circuit develops inside the kettle.

a

Calculate the normal operating current of the kettle. [1]

b

Explain why the short circuit causes the fuse to blow. [1]

Solutions

5QuestionCharging by Friction Induction and ConductionConcept Practice

2 marks~3 minCriterion A

A student touches a negatively charged rod against a neutral metal sphere, then removes the rod.

a

Explain the movement of electrons between the rod and the sphere during contact. Use the terms transfer, negative charge, repel, and neutral in your answer. [1]

b

State and justify the final charge of the sphere after the rod is removed. [1]

Solutions

6QuestionElectrical Components and their symbolsConcept Practice

3 marks~5 minCriterion A

The graph below shows the current–voltage (

I

–

V

) characteristics of a fixed resistor and an LED. The fixed resistor produces a straight line through the origin; the LED produces a curve that rises slowly at first, then steeply beyond a threshold voltage.

a

State Ohm's Law and write its mathematical form. [1]

b

Explain why the fixed resistor obeys Ohm's Law, with reference to the shape of its

I

–

V

graph. [1]

c

Explain why the LED does not obey Ohm's Law, referring to both the shape of its

I

–

V

graph and what this reveals about its resistance. [1]

Solutions

7QuestionAdvantages and Applications of Each TypeConcept Practice

2 marks~3 minCriterion B

Outline the steps of an experiment to compare the brightness of bulbs in series and parallel circuits. The apparatus diagram shows two circuits: one with three identical bulbs (A, B, C) connected in series to a battery, and another with three identical bulbs (D, E, F) connected in parallel to an identical battery. Each bulb is labeled. Describe the procedure in sequence, including what you would observe and how you would record the brightness.

Solutions

8QuestionElectrical Components and their symbolsConcept Practice

2 marks~3 minCriterion D

In the global electronics industry, engineers in different countries routinely share circuit schematics to manufacture and assemble devices.

a

Identify one real-world context in the electronics industry where standardized electrical symbols are essential. [1]

b

Explain one consequence that could arise if electrical symbols were not standardized across countries. [1]

Solutions

9QuestionCurrent and Voltage in Parallel CircuitsConcept Practice

2 marks~3 minCriterion C

A hospital monitoring system uses a parallel circuit to power three independent sensors. Each sensor is connected across the same two rails. A voltmeter connected across Sensor 1 reads

6 \, \text{V}

.

a

Deduce the voltage across Sensor 2 and across Sensor 3. [1]

b

A technician proposes replacing the parallel arrangement with a series arrangement to "keep the voltage the same across every sensor." Evaluate this proposal. [1]

Solutions

10QuestionCalculating Resistance in Series and ParallelConcept Practice

2 marks~3 minCriterion C

Describe the trend shown in the line graph that plots total resistance (R) on the y-axis against the number of identical resistors (N) added in series on the x-axis. Use scientific language to explain why this trend occurs.

Solutions

11QuestionPractical Circuits and Energy ConsumptionConcept Practice

2 marks~3 minCriterion D

A household currently uses ten 60 W incandescent bulbs for 5 hours each day. The family is considering replacing them with equivalent LED bulbs, each rated at 10 W.

a

Calculate the reduction in energy consumed per day when switching from incandescent to LED bulbs. Express your answer in kilowatt-hours (kWh). [1]

b

Discuss one environmental consequence of this reduction in daily energy consumption, referring to how electricity is generated in most countries. [1]

Solutions

12QuestionCalculating Resistance in Series and ParallelConcept Practice

2 marks~3 minCriterion A

A string of decorative lights is wired in series. During a festival display, one bulb burns out.

a

Explain what happens to the remaining bulbs when one bulb fails in a series circuit. [1]

b

Explain one advantage of wiring a home lighting system in parallel rather than in series. [1]

Solutions

13QuestionCalculating Resistance in Series and ParallelConcept Practice

4 marks~6 minCriterion B

A solar-powered irrigation controller uses three resistors —

10\ \Omega

,

15\ \Omega

, and

30\ \Omega

— connected in parallel to limit current to different valve solenoids. Study the circuit diagram provided.

a

State how voltage is distributed across resistors connected in parallel. [1]

b

Calculate the total resistance of the three-resistor parallel combination. [2]

c

A fourth solenoid branch is added in parallel. Evaluate the effect on the total resistance of the circuit, justifying your answer with reference to the parallel resistance formula. [1]

Solutions

14QuestionTransformers and their workingAssessment Practice

5 marks~8 minCriterion D

A student builds a step-down transformer for a school project using a laminated iron core and copper windings. The input power is 120 W and the output power is 108 W.

a

Calculate the efficiency of this transformer. Show your working. [2]

b

Explain why the efficiency is less than 100%, referring to specific energy losses in the transformer and how the laminated core and copper windings reduce these losses. [2]

c

Evaluate the use of laminated cores in real-world power distribution systems, considering energy savings, cost, and heat dissipation. [1]

Solutions

15QuestionUses of Electromagnets in Real LifeAssessment Practice

6 marks~9 minCriterion A

An experiment determines the relative permeability of iron. A solenoid is wound with 200 turns per metre and connected to a variable current supply. The magnetic field strength

B

inside the solenoid is measured for different currents

I

, first with an iron core, then with an air core. Both datasets produce straight lines through the origin on a

B

–

I

graph. The relationship governing the field is

B = \mu_0 \mu_r n I

.

The gradient for the air core is

2.51 \times 10^{-4}

T A

^{-1}

. The gradient for the iron core is

0.628

T A

^{-1}

.

a

State the value of the permeability of free space

\mu_0

. [1]

b

Deduce the number of turns per metre

n

of the solenoid from the air-core gradient, and comment on whether this is consistent with the experimental setup. [2]

c

Analyse both gradients to determine the relative permeability

\mu_r

of iron, and evaluate what this value reveals about iron as a core material for an electromagnet. [3]

Solutions

16QuestionUses of Electromagnets in Real LifeAssessment Practice

3 marks~5 minCriterion B

A student builds an electromagnet by wrapping a coil of wire around an iron core and connecting it to a power supply. She uses a magnetic field probe to measure field strength

B

at several distances

r

from the end of the core. Her results are shown in the graph below.

a

Describe the trend shown in the graph. [1]

b

State the mathematical relationship between

B

and

r

illustrated by the graph. [1]

c

Explain why the field strength drops much more steeply close to the core than far from it. [1]

Solutions

17QuestionMagnetic Field Around a Bar MagnetAssessment Practice

3 marks~5 minCriterion B

The table below shows measurements of magnetic field strength

B

near the north pole of a bar magnet.

d

(cm): 2, 4, 6, 8

B

(mT): 8.0, 2.0, 0.9, 0.5

a

Describe the trend shown by the data. [1]

b

When

d

doubles from 2 cm to 4 cm,

B

decreases by a factor of 4. Deduce what this suggests about the mathematical relationship between

B

and

d

. [1]

c

Explain, using the concept of magnetic field lines, why

B

decreases with increasing distance from the north pole. [1]

Solutions

18QuestionForce acting on current carrying wire in external magnetic fieldAssessment Practice

6 marks~9 minCriterion C

A student investigates the magnetic force on a current-carrying wire in a uniform magnetic field. The wire length is fixed at

L = 0.10

m and the magnetic flux density is

B = 0.50

T. The current

I

is varied and the force

F

is measured using a digital balance. Results are shown below.

$I$ (A)	1.0	2.0	3.0	4.0
Experimental $F$ (N)	0.048	0.102	0.155	0.196
Theoretical $F$ (N)	0.050	0.100	0.150	0.200

The percentage discrepancy is defined as

\left|\dfrac{F_{\text{exp}} - F_{\text{theo}}}{F_{\text{theo}}}\right| \times 100\%

.

a

Calculate the percentage discrepancy for each of the four trials. [2]

b

The experimental values are all lower than the theoretical values. Deduce one systematic error that would consistently reduce the measured force below the value predicted by

F = BIL

, and explain the mechanism by which it produces this effect. [2]

c

Evaluate whether the complete set of experimental results supports the model

F = BIL

. [2]

Solutions

19QuestionElectric Fuses and Circuit BreakersAssessment Practice

12 marks~18 minCriterion C

A student investigates how the operating current of common household appliances affects the choice of fuse rating required for safe operation. The student records the following data:

Appliance: Lamp	Operating current: $0.3\ \text{A}$	Fuse rating: $1\ \text{A}$
Appliance: Phone charger	Operating current: $0.5\ \text{A}$	Fuse rating: $1\ \text{A}$
Appliance: Television	Operating current: $1.8\ \text{A}$	Fuse rating: $3\ \text{A}$
Appliance: Kettle	Operating current: $8.7\ \text{A}$	Fuse rating: $10\ \text{A}$
Appliance: Washing machine	Operating current: $11.5\ \text{A}$	Fuse rating: $13\ \text{A}$

All appliances operate on a

230\ \text{V}

mains supply.

a

State the independent variable and the dependent variable in this investigation. [2]

b

The mains voltage is kept constant throughout the investigation. Explain why controlling this variable is necessary for a fair test. [2]

c

Describe the pattern between operating current and fuse rating shown in the data. Support your answer with values from the table. [3]

d

A hairdryer operates at

4.6\ \text{A}

. Deduce a suitable fuse rating for the hairdryer and justify your choice using the pattern in the data. [3]

e

Evaluate the consequences of fitting a fuse with a rating that is too high for an appliance operating at

11.5\ \text{A}

, such as the washing machine. [2]

Solutions

20QuestionDangers of Overloading and Short CircuitsAssessment Practice

6 marks~9 minCriterion D

A household extension cord is rated for a maximum current of 5 A. It is protected by a 10 A fuse and powers a 2400 W heater and a 600 W television, both connected to a 240 V mains supply.

a

Calculate the total current drawn by the heater and television when both are operating. [2]

b

Deduce whether the 10 A fuse provides adequate protection for the extension cord. [2]

c

Evaluate the effectiveness of using only a fuse to protect against all electrical hazards in this circuit, referring to both overload and short-circuit conditions. [2]

Solutions

21QuestionHousehold Wiring and Power RatingsAssessment Practice

5 marks~8 minCriterion B

A student investigates a fixed-resistance household heater connected to a variable power supply. Current

I

and power

P

are recorded below.

I

(A): 0.5, 1.0, 1.5, 2.0, 2.5, 3.0

P

(W): 30, 120, 270, 480, 750, 1080

a

Calculate

I^2

for each data point and show that

P

is proportional to

I^2

. [2]

b

Use the relationship

P = I^2 R

to determine the resistance

R

of the heater. Show your working and include units. [2]

c

The heater is rated as safe up to 1000 W. Analyse whether operating the heater at

I = 3.0

A poses a safety risk, and justify your reasoning using your calculated value of

R

. [1]

Solutions

22QuestionHousehold Wiring and Power RatingsAssessment Practice

8 marks~12 minCriterion D

A homeowner runs a single 230 V circuit protected by a 15 A circuit breaker. A 1500 W kettle and a 1000 W microwave are already connected. The homeowner wishes to add a 3000 W electric heater to the same circuit.

a

Show that the total current drawn when all three appliances operate simultaneously at their rated power exceeds the circuit breaker rating. Use

P = IV

. [2]

b

Explain how a circuit breaker with an appropriate current rating protects the household circuit in this situation. [2]

c

Analyse the risks of operating all three appliances simultaneously on this circuit, and evaluate whether the circuit breaker alone is sufficient to ensure safety, given that appliance power consumption fluctuates during operation. [4]

Solutions

23QuestionDangers of Overloading and Short CircuitsAssessment Practice

4 marks~6 minCriterion C

A house is wired so that two lamps, Lamp 1 (60 W) and Lamp 2 (100 W), are connected in parallel across a 230 V mains supply. Each branch has its own switch.

a

State the voltage across each lamp. [1]

b

The total current drawn from the supply is 0.70 A. Lamp 1 draws 0.26 A. Deduce the current through Lamp 2. [1]

c

A student claims that parallel wiring is always preferable to series wiring for domestic appliances. Discuss this claim, referring to at least two electrical properties of parallel circuits. [2]

Solutions

24QuestionEarth Wires and Electrical GroundingAssessment Practice

10 marks~15 minCriterion A

A student investigates the safety of a metal-cased electrical appliance. A fault causes the live wire to touch the metal casing. The circuit contains:

- mains voltage:

230 \text{ V}

- appliance wiring resistance:

0.5 \ \Omega

- earth wire resistance:

0.2 \ \Omega

- human body resistance:

1000 \ \Omega

- fuse rating:

5 \text{ A}

(in the live wire)

a

The earth wire is disconnected. A person touches the metal casing and becomes the only path to earth. Calculate the current through the person. [2]

b

The earth wire is reconnected. The earth wire and the person now form two parallel paths between the casing and earth. Calculate the current through the earth wire and the current through the person. Show your working clearly. [3]

c

Using your results from (a) and (b), analyse why connecting the earth wire protects the user. In your answer, refer to the path of least resistance, current division, and the fuse rating. [5]

Solutions

25QuestionDangers of Overloading and Short CircuitsAssessment Practice

6 marks~9 minCriterion B

A student investigates how current affects the time for wire insulation to melt. Five wires of different gauges are tested; each carries a fixed current until its insulation melts.

Current (A)	15	10	6	4	2.5
Time to melt (s)	5	12	30	60	120

a

On the axes provided, construct a graph of time to melt (vertical axis) against current (horizontal axis). [2]

b

Deduce a mathematical rule linking time to melt and current. Show the calculations you used to arrive at your rule. [2]

c

A fuse wire in a household circuit carries 8 A. Evaluate whether this wire's insulation will melt within 20 seconds, using your rule and the pattern in the data. [2]

Solutions

26QuestionUnderstanding Static Charge and DischargeAssessment Practice

3 marks~5 minCriterion C

The graph shows the charge

Q

(in microcoulombs,

\mu\text{C}

) on the dome of a Van de Graaff generator against time

t

(in seconds) after switch-on. The charge rises steeply from

0

to approximately

8\ \mu\text{C}

in the first

2\ \text{s}

, then gradually flattens, approaching a maximum of

10\ \mu\text{C}

after about

6\ \text{s}

.

a

State one reason why the charge on the dome increases rapidly during the first

2\ \text{s}

. [1]

b

Explain why the rate of charge increase slows as

Q

approaches

10\ \mu\text{C}

. [1]

c

Discuss why the charge reaches a constant maximum value even though the generator continues to operate. [1]

Solutions

27QuestionCharging by Friction Induction and ConductionAssessment Practice

3 marks~5 minCriterion A

A student brings a negatively charged rod near — but not touching — the metal cap of an uncharged gold-leaf electroscope. While the rod remains in place, the student momentarily touches the cap with a finger to ground it, then removes the finger. The rod is removed last.

a

Deduce the final net charge on the electroscope. [1]

b

Explain, using the law of conservation of charge, how this charge arose during the grounding step. [1]

c

Explain how the final charge is distributed across the electroscope and what this distribution causes the gold leaves to do. [1]

Solutions

28QuestionCharging by Friction Induction and ConductionAssessment Practice

4 marks~6 minCriterion B

A student rubs pairs of materials together and records which becomes positively and which becomes negatively charged. A triboelectric series diagram is provided, ranking materials from those most likely to lose electrons (top) to those most likely to gain electrons (bottom).

a

State what the position of a material in the triboelectric series indicates about its tendency to lose or gain electrons. [1]

b

Explain which material becomes negatively charged when two materials from different positions in the series are rubbed together. [1]

c

Analyse how the separation between two materials in the triboelectric series affects the magnitude of charge produced, and justify your reasoning in terms of electron affinity. [2]

Solutions

29QuestionElectric Conductors and Insulators UsageAssessment Practice

5 marks~8 minCriterion D

A student investigates a cylindrical copper wire of length

L = 2.00 \, \text{m}

and cross-sectional area

A = 1.00 \times 10^{-6} \, \text{m}^2

. She measures the potential difference across the wire for several currents and plots voltage

V

against current

I

. The graph is a straight line through the origin with gradient

0.0340 \, \text{V A}^{-1}

.

The resistivity of a conductor is given by

R = \dfrac{\rho L}{A}

.

The accepted resistivity of copper is

1.68 \times 10^{-8} \, \Omega \cdot \text{m}

.

a

Deduce the resistance of the wire from the graph. [1]

b

Calculate the resistivity

\rho

of the copper wire. [2]

c

Analyse whether the experimental result is consistent with the accepted value of copper's resistivity, justifying your answer with a quantitative comparison. [2]

Solutions

30QuestionElectric Field Concepts IntroductoryAssessment Practice

6 marks~9 minCriterion B

A student investigates the electric field around a small charged sphere by measuring field strength

E

at several distances

d

from the sphere's centre.

Distance

d

(m): 0.10, 0.20, 0.30, 0.40

Field strength

E

(N/C): 900, 225, 100, 56.25

a

Analyse the data to describe how electric field strength varies with distance. Support your answer with at least two calculations from the table. [2]

b

Deduce the electric field strength at

d = 0.50

m. Show your reasoning clearly. [2]

c

Justify a general mathematical relationship between

E

and

d

that is consistent with all four data points, and evaluate whether this relationship is physically reasonable for a small charged sphere. [2]

Solutions

31QuestionHazards and Uses of Static ElectricityAssessment Practice

6 marks~9 minCriterion C

A negatively charged plastic rod is brought close to thin streams of three liquids falling from a burette. The deflection angles recorded are:

Water (polar): 15°
Ethanol (slightly polar): 8°
Oil (non-polar): 0°

Acetone is a polar molecule with a dipole moment similar to that of water.

a

Deduce the relationship between molecular polarity and deflection angle shown by the data. [1]

b

Justify a predicted deflection angle for acetone, using the data above. [2]

c

Explain, in terms of molecular dipoles and charge distribution, why a polar liquid stream is attracted toward a negatively charged rod. [3]

Solutions

32QuestionElectric Conductors and Insulators UsageAssessment Practice

6 marks~9 minCriterion D

A government in a developing country must choose between copper and aluminium wiring for a new affordable housing project. Copper has electrical resistivity

\rho_{\text{Cu}} = 1.7 \times 10^{-8} \, \Omega \cdot \text{m}

; aluminium has

\rho_{\text{Al}} = 2.8 \times 10^{-8} \, \Omega \cdot \text{m}

. Copper mining causes significant habitat destruction and water pollution. Aluminium is lighter, recyclable using only 5% of the energy needed for primary production, and has a lower mining impact.

a

Using the resistivity values, explain which material offers better electrical performance for identical wire dimensions. [2]

b

Analyse the environmental and social trade-offs that make aluminium a viable alternative despite its higher resistivity. [2]

c

Evaluate which material the government should choose, considering electrical performance, environmental impact, and the socioeconomic context of affordable housing. [2]

Solutions

33QuestionConstructing Simple Electrical CircuitsAssessment Practice

5 marks~8 minCriterion A

A student builds a circuit to investigate an unknown resistor, measuring current

I

for different voltages

V

. The results are shown below.

V

(V): 0, 1.0, 2.0, 3.0, 4.0, 5.0, 6.0

I

(A): 0, 0.20, 0.40, 0.60, 0.80, 1.00, 1.20

A straight line of best fit is drawn through the origin on an

I

–

V

graph.

a

Deduce the resistance of the unknown resistor using the gradient of the

I

–

V

graph. [2]

b

Explain why the gradient of an

I

–

V

graph equals

\frac{1}{R}

, rather than

R

itself. [1]

c

The resistor is now connected in series with an identical second resistor. Analyse how this change affects the gradient of the

I

–

V

graph and the current at

V = 7.5

V. [2]

Solutions

34QuestionCurrent and Voltage in Parallel CircuitsAssessment Practice

4 marks~6 minCriterion B

A student builds a parallel circuit at a constant supply voltage of 6.0 V. Each branch contains an identical resistor of 15 Ω. The student adds branches one at a time and records the total current.

a

Interpret the pattern shown in the graph between the number of branches and the total current. [1]

b

Deduce the total current when 4 branches are connected. Show your reasoning. [1]

c

Analyse the relationship between total resistance and number of branches. Justify whether this relationship is linear or non-linear, and explain what this means for how resistance changes as the circuit grows. [2]

Solutions

35QuestionMeasuring Current and Voltage with Ammeters and VoltmetersAssessment Practice

5 marks~8 minCriterion C

A student builds a parallel circuit with a 12 V battery and three resistors:

R_1 = 10\ \Omega

,

R_2 = 20\ \Omega

, and

R_3 = 30\ \Omega

. Ammeter

A_1

is placed in the main branch; ammeters

A_2

,

A_3

, and

A_4

are placed in the branches containing

R_1

,

R_2

, and

R_3

respectively. The student records:

A_1 = 2.2\ \text{A}

,

\quad A_2 = 1.2\ \text{A}

,

\quad A_3 = 0.8\ \text{A}

,

\quad A_4 = 0.4\ \text{A}

a

Calculate the expected current through each resistor using Ohm's law. [2]

b

Apply Kirchhoff's Current Law to calculate the expected total current, and justify whether

A_1

is consistent with this value. [1]

c

Evaluate which ammeter reading is inconsistent with theory, and explain what this discrepancy suggests about the measurement or the circuit. [2]

Solutions

36QuestionConstructing Simple Electrical CircuitsAssessment Practice

8 marks~12 minCriterion D

A non-profit organisation installs solar home systems in a rural off-grid community. Each system uses a 12 V battery and three 12 V LED bulbs, each rated at 6 W, connected in parallel. The total wire resistance between the battery and the bulbs is 0.8 Ω. Assume the bulbs behave as ohmic resistors.

a

Calculate the total current drawn from the battery and the voltage drop across the wires. Use

P = IV

and

V = IR

. [2]

b

Explain how this voltage drop affects the power delivered to the bulbs and the energy efficiency of the system. [2]

c

The organisation chose thin, high-resistance wires to reduce upfront costs for low-income households. Discuss the ethical trade-off between affordability and system reliability, and analyse how poor performance may affect long-term community trust in off-grid solar technology. [3]

d

Justify one design change that would improve system performance without making the system unaffordable. [1]

Solutions

37QuestionGraphing V-I Characteristics for Resistors and BulbsAssessment Practice

4 marks~6 minCriterion A

A student investigates a fixed resistor by recording voltage and current. The data are plotted on a voltage–current (

V

–

I

) graph, and a best-fit line is drawn through the origin. The gradient of this line is

12 \, \text{V A}^{-1}

.

a

Deduce the resistance of the resistor from the gradient of the

V

–

I

graph. [1]

b

Show that the voltage across the resistor when the current is

2.2 \, \text{A}

is approximately

26 \, \text{V}

. [1]

c

The student repeats the experiment replacing the fixed resistor with a filament bulb. Analyse how the

V

–

I

graph for the bulb would differ from that of the resistor, and explain what this reveals about how resistance changes with temperature. [2]

Solutions

38QuestionPractical Circuits and Energy ConsumptionAssessment Practice

6 marks~9 minCriterion D

A household replaces a 60 W incandescent bulb with a 10 W LED bulb. Both produce 800 lumens of light output. The bulbs are each used for 1000 hours, and electricity costs 0.15 dollars per kWh.

a

Calculate the electrical energy consumed by each bulb over 1000 hours. Express your answers in kWh and show your working. [2]

b

Calculate the total electricity cost of operating each bulb over 1000 hours. Show your working. [2]

c

A student claims that switching to LED bulbs is always the better environmental choice. Evaluate this claim using your results from (a) and (b) and your knowledge of energy conversion in both bulb types. [2]

Solutions

39QuestionCalculating Resistance in Series and ParallelAssessment Practice

4 marks~6 minCriterion B

A heating engineer tests a circuit in which a 24 V battery is connected in series to three resistors:

R_1 = 2\,\Omega

,

R_2 = 4\,\Omega

, and

R_3 = 6\,\Omega

. The circuit diagram is shown below.

a

Calculate the total resistance of the circuit. [1]

b

Deduce the current through

R_2

, justifying why a single current value applies to all three resistors. [1]

c

Analyse the power dissipated by each resistor and evaluate whether the largest resistor always dissipates the most energy per second in a series circuit. [2]

Solutions

40QuestionOhms Law V = IRAssessment Practice

8 marks~12 minCriterion C

A student investigates a resistor by measuring the current

I

through it at increasing potential differences

V

.

V

(V): 0.0, 1.0, 2.0, 3.0, 4.0, 5.0

I

(A): 0.00, 0.20, 0.40, 0.61, 0.79, 1.01

a

On the provided graph, construct a best-fit straight line through the origin. [2]

b

Deduce the resistance of the resistor from the gradient of your best-fit line, showing your working clearly. [2]

c

Analyse the data to evaluate whether this resistor behaves ohmically across the full voltage range. Use calculated values to support your conclusion. [4]

Solutions

Electricity and Magnetism — Free MYP4 Physics Practice Questions