Skip to content

Draw a labelled diagram to… (Class 10 Science 2024, Q25a)

questionbuddy.in/q/cbse-10-science-2024-31-3-1-q25a-draw-labelled-diagram-pattern-magnetic

ScienceCBSE Class 10 · Board exam 2024, set 31/3/1 · 2 marks · Very short answer

CBSE Class 10 Science 2024: question 25(a)

Set in the CBSE Class 10 board exam of 2024, paper 31/3/1, section B, question 25(a), for 2 marks. Try it first; the hints and our step-by-step solution are below.

Q25(a) · 2 marks · Very short answerMagnetic Effects of Electric Current

Draw a labelled diagram to show the pattern of magnetic field lines produced due to a current carrying straight conductor. Mark on it the direction of current in the conductor and the direction of magnetic field lines.

Source: official question paper from cbse.gov.in (PDF). See it in the full 2024 board paper, set 31/3/1.

Hints

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

Hint 1

Recall the NCERT activity with iron filings sprinkled on cardboard around a vertical wire.

Hint 2

What shape do the field lines take around a straight wire?

Hint 3

Use the right-hand thumb rule to decide the arrow direction on the circles.

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.

  1. Diagram (describe/draw): Draw a straight vertical wire XY passing through a horizontal cardboard sheet. Connect it in a circuit with a battery, key K, a variable resistance and an ammeter. On the cardboard, draw concentric circles centred on the wire. These are the magnetic field lines. They lie closer together near the wire and farther apart away from it. Label: conductor, cardboard, magnetic field lines, battery, key.

    1 mark

  2. Direction of current: Mark an arrow on the wire. Take the current flowing vertically upward (from Y to X), i.e. from the + terminal of the battery round the circuit.

    ½ mark

  3. Direction of field: By the right-hand thumb rule, with the thumb pointing along the upward current, the curled fingers give the field direction. The field lines are therefore anticlockwise when viewed from above. Mark arrows on the circles accordingly. (If the current is downward, the circles become clockwise.)

    ½ mark

Answer: Concentric circular field lines centred on the wire. For an upward current they are anticlockwise when seen from above (right-hand thumb rule).

Where the marks are

  • Correct diagram: straight conductor through cardboard with concentric circles (1 mark)
  • Direction of current marked on conductor (½ mark)
  • Direction of field lines consistent with right-hand thumb rule (½ mark)

Revise the chapter

Practise this chapterBoard-style questions from Magnetic Effects of Electric Current, one at a time, marked against the answer key and marking points.Back to the full paper2024 board paper, set 31/3/1: 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.