Grade 10 Physical Sciences · Electricity and Magnetism

Define circuit terms and Ohm's law

Give the exact meaning of circuit words like current, potential difference, emf and resistance, or state Ohm's law.

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Ohm's Law Grade 11 Electric Circuits (Electricity grade 11 & 12)Miss Martins Maths and Science

Electric circuits Internal resistance Intro: PHYSICS grade 11 and 12Miss Martins Maths and Science

Circuits grade 10 | Part 1Kevinmathscience

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Question 8.1 · November 2025 · Paper 1 · National (DBE) · 2 marks

Two identical headlights,

L_{1}

and

L_{2}

, and a starter motor, M, of a car are connected to a battery, as shown in the circuit diagram below. The resistance of each headlight is

12 Ω

, while the resistance of the starter motor is

0, 1 Ω

. The emf (

ε

) and internal resistance (r) of the battery are unknown.

The ammeters and the connecting wires have negligible resistance, while the voltmeter has a high resistance. Switches

S_{1}

and

S_{2}

are initially open. Diagram for this question

8.1 Define the term emf.(2)

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More past paper questions: define circuit terms and ohm's law

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3. Question 8.1 · November 2024 · Paper 1 · National (DBE) · 2 marks
$L_{1}$ and $L_{2}$ are two light bulbs that have the following ratings:

$L_{1}$ : $36$ W ; $20$ V and $L_{2}$ : $48$ W ; $32$ V

The two bulbs are connected as shown in the circuit diagram below. The battery has an internal resistance of $0, 6 Ω$ while the conducting wires and the ammeters have negligible resistance. $R_{1}$ and $R_{2}$ are resistors.
8.1 Define the term power.(2)
Show the memo (1 tick)Memo
1. ✓
  Definition of powerThe rate at which work is done/dissipated OR energy transferred OR work done per unit time.
  2 marks · Define circuit terms and Ohm's law
4. Question 8.1 · November 2023 · Paper 1 · National (DBE) · 2 marks
The circuit diagram below shows a battery with an emf of $12$ V and an internal resistance of $0, 5 Ω$ connected to three resistors, a light bulb, a switch, an ammeter and connecting wires. The ammeter and connecting wires have negligible resistance.
8.1 State Ohm's law in words.(2)
Show the memo (1 tick)Memo
1. ✓
  Ohm's lawThe potential difference (voltage) across a conductor is directly proportional to the current in the conductor at constant temperature.
  
  OR
  
  The current in a conductor is directly proportional to the potential difference (voltage) across the conductor if temperature is constant.
  
  OR
  
  The ratio of potential difference to current is constant provided the temperature remains the same.
  2 marks · Define circuit terms and Ohm's law
5. Question 8.1 · May/June 2023 · Paper 1 · National (DBE) · 2 marks
A battery with unknown emf ( $ε$ ) and unknown internal resistance (r) is connected to three resistors, a high-resistance voltmeter, two switches and two ammeters of negligible resistance, as shown below.
8.1 State Ohm's law in words.(2)
Show the memo (1 tick)Memo
1. ✓
  Ohm's lawThe potential difference across a conductor is directly proportional to the current in the conductor at constant temperature (provided all other physical conditions remain constant).
  
  OR
  
  The ratio of potential difference to current is constant at constant temperature.
  
  OR
  
  The current in a conductor is directly proportional to the potential difference across the conductor at constant temperature (provided all other physical conditions remain constant).
  2 marks · Define circuit terms and Ohm's law
6. Question 8.1 · May/June 2022 · Paper 1 · National (DBE) · 2 marks
In the circuit below a battery of UNKNOWN emf and an internal resistance of $0, 5 Ω$ is connected to two resistors of $4 Ω$ and $8 Ω$ each, and a resistor R of unknown resistance.

Ignore the resistance of the connecting wires.
8.1 The three external resistors are ohmic conductors.

Explain the meaning of the term ohmic conductor.(2)
Show the memo (1 tick)Memo
1. ✓
  Ohmic conductorA conductor (resistor) which obeys Ohm's law.
  
  OR
  
  V always directly proportional to I at constant temperature.
  
  OR
  
  $\frac{V}{I}$ = constant at constant temperature.
  
  OR
  
  A conductor for which the resistance remains constant at constant temperature when voltage or current change.
  2 marks · Define circuit terms and Ohm's law

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