A conducting rod lies across two horizontal, parallel conducting rails connected to a battery and a switch. The rod is positioned in the region between the North and South poles of a magnet, with the North pole above the rod and the South pole below it. When the switch is closed, the rod experiences a force and moves to the right. Which of the following modifications would cause the rod to move to the left?
Use a stronger magnet with the poles in the same positions.
Reverse the connections to the battery terminals and exchange the positions of the magnet's poles.
Reverse the connections to the battery terminals while keeping the magnet poles in their original positions.
Turn the conducting rod around so its ends are swapped.
19 exam-style questions on CIE IGCSE Physics 4.5.4a Force on a current-carrying conductor. Each one has a worked solution and a mark scheme showing where the marks go.