For Class 8, 9 & 10

Foundation - a strong base in Physics, Chemistry, Maths & Biology

Concept-first questions with clear model answers across all four subjects, aligned to NCERT. Start early, build the habit, and walk into your board exams, NEET and JEE already ahead.

Showing 1 question in Physics for Class 10. Tap a card to reveal the answer.

PhysicsMagnetic Effects of Electric Currenteasy

State the right-hand thumb rule for the magnetic field around a straight current-carrying wire.

Reveal answer ↓

What it is

A current in a straight wire creates circular magnetic field lines around it.

Answer

If you hold the straight conductor in your right hand with the thumb pointing in the direction of the current, the curled fingers show the direction of the concentric circular magnetic field lines around the wire.

  • Thumb -> direction of current
  • Curled fingers -> direction of field
  • Field lines are concentric circles around the wire

Why learn this

It's the principle behind electromagnets, electric motors, bells and MRI machines.

💡 Memory trick

Right hand: thumb = current, curled fingers = the circular magnetic field.