ScienceCBSE Class 10 · Board exam 2024, set 31/2/1 · 1 mark · MCQ

CBSE Class 10 Science 2024: question 15

Set in the CBSE Class 10 board exam of 2024, paper 31/2/1, section A, question 15, for 1 mark. Try it first; the hints and our step-by-step solution are below.

Q15 · 1 mark · MCQElectricity

Study the I-V graph for three resistors of resistances $R_{1}$ , $R_{2}$ and $R_{3}$ and select the correct statement from the following :

(A) $R_{1} = R_{2} = R_{3}$
(B) $R_{1} > R_{2} > R_{3}$
(C) $R_{3} > R_{2} > R_{1}$
(D) $R_{2} > R_{3} > R_{1}$

Figure in the paper: Graph of current I (ampere) on the vertical axis against potential difference V (volts) on the horizontal axis. Three straight lines pass through the origin, labelled R1 (steepest), R2 (intermediate) and R3 (least steep). See it in the official paper.

Source: official question paper from cbse.gov.in (PDF). See it in the full 2024 board paper, set 31/2/1.

Hints

Open one hint at a time and try again before the next.

Hint 1

Write Ohm's law with I as the subject.

Hint 2

What does the slope of this graph represent?

Step-by-step solution

Each step shows the marks it earns, as an examiner would award them. Checked by an independent re-solve from the question paper.

From $I = \frac{V}{R}$ , the slope of an I–V graph is $\frac{1}{R}$ . A steeper line means a smaller resistance.
½ mark
R1 is steepest and R3 is least steep, so $R_{3} > R_{2} > R_{1}$ . Option (C) is correct.
½ mark

Answer: $R_{3} > R_{2} > R_{1}$ : option (C)

Where the marks are

Relates slope to $1/ R$ and selects option (C) (1 mark)

Revise the chapter

Chapter: Electricity (notes, formulas, where marks are lost and every past question)

Practise this chapterBoard-style questions from Electricity, one at a time, marked against the answer key and marking points.Back to the full paper2024 board paper, set 31/2/1: every question, by section.

The question is transcribed from the official paper; figures are described in words. The solution, hints and chapter tag are ours. Spotted an error? Write tosupport@questionbuddy.in.

CBSE Class 10 Science 2024: question 15

Hints

Step-by-step solution

Revise the chapter

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