# Lorentz force and cosmic rays

1. Nov 27, 2008

### scienceman111

I am trying to calculate the strength of the magnetic field ( in teslas ) that would be needed to deflect cosmic rays going about 99% the speed of light.

using the lorents force

http://en.wikipedia.org/wiki/Lorentz_force

I replaced force with mass times acceleration

I canceled the cross product because for this case pretend that the cosmic ray hits the magnetic field perpendicularly(eliminating the cross product)

the variable E is also canceled because I am not applying an electric force

so I end up with B= (mass times accleration) divided by (the charge in coloumbs times the velocity (99% the speed of light))

but correct me if I am wrong. I have the accleration of cosmic rays to be 10,000 m/s squared until it reaches its maximum speed

but because I am dividing by the spped of light(almost)

I end up with a (insert a huge decimal number here) Teslas

which must be incorrect because it would take many teslas to deflect cosmioc rays