Calculate the total current in the circuit.
About this question
Question 9.2 of Technical Sciences Grade 12 Paper 1, NSC Preparatory Examination (Eastern Cape DoE, September 2025). It tests the Term 3 ATP topic Electric Circuits Power.
- TermTerm 3
- ATP topicElectric Circuits Power
- PaperPaper 1
- Marks4 marks for the method (formula and substitution) and the correct final answer
Four resistors are connected to a battery with a terminal potential difference of \(12\ \text{V}\), as shown in the diagram.
The \(25\ \Omega\) and \(30\ \Omega\) resistors are in series: \(R_s = 25 + 30 = 55\ \Omega\). This is in parallel with the \(80\ \Omega\) resistor:
\[ \frac{1}{R_p} = \frac{1}{55} + \frac{1}{80} \Rightarrow R_p = 32{,}59\ \Omega \]\[ R_T = R_p + 20 = 52{,}59\ \Omega \]\[ I = \frac{V}{R_T} = \frac{12}{52{,}59} \]\( I = 0{,}23\ \text{A} \)
More Questions On Electric Circuits Power
D: Volt.
Emf is measured in volts, the same unit as potential difference.
Time used in the month: \( \frac{7{,}5}{60} \times 30 = 3{,}75\ \text{h} \).
\[ E = P t = (1{,}5)(3{,}75) = 5{,}625\ \text{kWh} \]\[ \text{Cost} = 5{,}625 \times 3{,}20 \]\( \text{Cost} = \text{R}18{,}00 \)
\( W = 126{,}96\ \text{J} \)
The potential difference across a conductor is directly proportional to the current in it, at constant temperature.