CBSE 2025 · Region 5 · Set 3 · Q5 · 1 mark
Four resistors, each of resistance $\displaystyle \mathrm{R}$ and a key $\displaystyle K$ are connected as shown in the figure. The equivalent resistance between points A and B when key K is open, will be:
Official answer
From CBSE’s own marking scheme for this paper.
(D)
$\displaystyle \frac{4 \mathrm{R}}{3}$
Current ElectricityKirchhoff’s RulesApplymcqmedium
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×
- An electric iron rated 2‧2 kW, 220V is operated at 110 V supply. Find: (i) its resistance, and (ii) heat…2026 · asked 3×
- In the given figure, three identical bulbs P, Q and S are connected to a battery. (i) Compare the brightness…2025 · asked 3×
CBSE Class 12 Physics past-paper question from the 2025board exam, with the answer as CBSE’s own marking scheme gives it. Where our answers come from.