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Current Electricity question

2023 · 6 Apr · Shift 2 · Q53

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Current Electricity
2023 · 6 Apr · Shift 2 · Q53

Current Electricity question

2023 · 6 Apr · Shift 2 · Q53

JEE MainPhysicsCurrent ElectricityMCQ+4 / −1

Figure shows a part of an electric circuit. The potentials at points

a, b

and

c

are

30 \mathrm{~V}, 12 \mathrm{~V}

and

2 \mathrm{~V}

respectively. The current through the

20 ~\Omega

resistor will be, JEE Main 2023 (Online) 6th April Evening Shift Physics - Current Electricity Question 72 English

JEE Main 2023 (Online) 6th April Evening Shift Physics - Current Electricity Question 72 English

A
0.2 A
B
0.6 A
C
0.4 A
D
1.0 A

View written solutionFree

Correct answer: C

Use the given potentials at the ends of the resistor

The current through a resistor depends only on the potential difference across it:

$I = \frac{V_1 - V_2}{R}$

From the figure/data, the $20\,\Omega$ resistor is connected between points $b$ and $c$ .

Given:

Potential at $b = 12\,\text{V}$
Potential at $c = 2\,\text{V}$
Resistance $R = 20\,\Omega$

Find the potential difference across the resistor

$\Delta V = V_b - V_c = 12 - 2 = 10\,\text{V}$

Apply Ohm's law

$I = \frac{\Delta V}{R} = \frac{10}{20} = 0.5\,\text{A}$

So, the current through the $20\,\Omega$ resistor is

$\boxed{0.5\,\text{A}}$

Compare with the given options

The options are:

A: $0.2\,\text{A}$
B: $0.6\,\text{A}$
C: $0.4\,\text{A}$
D: $1.0\,\text{A}$

None of these matches $0.5\,\text{A}$ .

Hence, the stored correct answer $\text{C}$ does not agree with the value obtained from Ohm's law using the stated node potentials.

It is likely that either:

the figure connection is different from the text-only interpretation, or
the stored answer is incorrect, or
one of the given potentials/options has a typo.

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