Question

The aurora is caused by electrons and protons from the Sun spiraling in along the direction of the Earth’s magnetic field. The typical speed of the electrons involved is about 0.5% of the speed of light. The magnitude of B near the Earth is approximately 30 ˆ 10 ́6 T.

1 What is the maximum radius of the circular part of these electrons’ motions around the field direction as they spiral into the atmosphere?

2 How long does it take for the electron to complete one full circle? You can assume that the component of their velocity in the direction of the field is negligible.

3 If we had a positron (a positively charged electron) enter the Earth’s atmosphere, how would its motion be different?

Please demonstrate what equation you used, and show your work

Answer 1