Our rating: False. Based on our research, we rate FALSE the claim that a compass wouldn't work if Earth is spherical. Compasses orient themselves to the Earth's magnetic field lines.

Similarly, the minimum value of sine theta is 0, when theta is 0 - so that means the current is parallel to the magnetic field lines. And in that case, there won't be any force on the wire at all.

When you purchase through links on our site, we may earn an affiliate commission. Here’s how it works. Earth's magnetic field, which protects the planet from huge blasts of deadly solar ...

New research hints at the biophysical underpinnings of their ability to use Earth’s magnetic field lines to find their way to their breeding and wintering grounds ...