CBSE 2024 · Region 4 · Set 2 · Q27 · 3 marks
Find the currents flowing through the branches AB and BC in the network shown.

Marking-scheme solution
Using Kirchhoff's voltage rule.
In closed loop ABMNA:
$\displaystyle -5 I_{1}+10\left(I-I_{1}\right)-5=0$ ……………………… ($\displaystyle 1$)
In closed loop ACDNA:
$\displaystyle -5 I-20 I+10-5-5 I_{1}=0$ ……………………….. ($\displaystyle 2$)
Solving eq ($\displaystyle 1$) and ($\displaystyle 2$):
$\displaystyle I_{1}=-\frac{3}{17} \mathrm{~A}$ and $\displaystyle I=\frac{4}{17} \mathrm{~A}$
Magnitude of current in arm AB $\displaystyle =\frac{3}{17} \mathrm{~A}$
Magnitude of current in arm BC $\displaystyle =\frac{4}{17} \mathrm{~A}$
Current ElectricityKirchhoff’s RulesApplyshort_answermedium
More from Current Electricity
- A steady current flows through a metallic wire whose area of cross-section increases continuously from one…2023 · asked 3×
- (i) Define mobility of electrons. Give its SI units. (ii) A steady current flows through a wire AB, as shown…2023 · asked 3×
- What is the order of magnitude of drift velocity of electrons in a conductor? Deduce the relation between the…2026 · asked 3×
- A student sets up the circuit as shown in the figure to find the value of unknown resistance X and records a…2026 · asked 3×
- What is meant by 'relaxation time' of free electrons in a conductor? Show that the resistance of a conductor…2024 · asked 3×
- Two batteries of emf's 3 V \& 6 V and internal resistances 0.2 Ω & 0.4 Ω are connected in parallel. This…2025 · asked 3×
- Four resistors, each of resistance R and a key K are connected as shown in the figure. The equivalent…2025 · asked 3×
- An electric iron rated 2‧2 kW, 220V is operated at 110 V supply. Find: (i) its resistance, and (ii) heat…2026 · asked 3×
CBSE Class 12 Physics past-paper question from the 2024board exam, with the answer as CBSE’s own marking scheme gives it. Where our answers come from.