Welcome to the most rewarding Physics forums. Here you earn rewards for discussing Physics. To ask a new question or start a new thread, click the ‘NEW’ button in the respective forum in the respective forums group. There are 3 forum groups: Physics, Suggest, and Support. For Physics related discussion, choose ‘Physics’. To suggest new ideas and features for ThePhysicist, choose ‘Suggest’. To seek support on issues faced on ThePhysicist, choose ‘Support’. To learn about rewards, visit Rewards
Why is the directio...

Share:
Clear all

# Why is the direction of the magnetic field inside a bar magnet from S to N?

0 Posts
1 Users
0 Likes
510 Views
0
Topic starter

As a convention, the field lines due to a permanent bar magnet have a direction at any point outside the magnet along the direction that a tiny magnetic compass needle shows. Since like magnetic poles repel and opposite poles attract, the compass north, $N_{com}$ always stays in a direction away from the bar north, $N_{bar}$ as long as the compass is outside the bar magnet.

However, if we drill a longitudinal tunnel through the bar magnet and insert our tiny compass, then $N_{com}$ will be towards $N_{bar}$.

Why?

Refer to this figure: