Earth as a Giant Magnet

In the picture

1. 1The bar magnet’s red end: one end of the model magnet inside the globe
2. 2The bar magnet’s blue end: the opposite end of the model magnet
3. 3The compass needle: the thin magnet that turns to align with the nearby field
4. 4The globe’s rotation axis: the line through the poles that the globe spins around

Examples

• A hiker uses a compass to keep walking north through fog.
• A phone’s compass app shows which way the phone is facing.

Quiz: Earth as a Giant Magnet (Age 14)

1. 1

   According to the card, what does a compass needle do with Earth’s magnetic field?

   • It points only along Earth’s rotation axis.
   • It stays fixed and ignores the field.
   • It turns until it lines up with the field.
2. 2

   How does the card compare Earth’s magnetic field?

   • To a huge bar magnet.
   • To a single magnetic pole at Earth’s centre.
   • To a small bar magnet on Earth’s surface.
3. 3

   Which statement about Earth’s magnetic field does the card support?

   • It is exactly aligned with Earth’s rotation axis.
   • It only exists at the poles.
   • It is tilted relative to Earth’s rotation axis.

The answers, each with its explanation, are in the app. This lesson has left the free week, so its quiz is part of the subscription.