Question

Magnetic fields at the surface of the sun can be strong enough to cause solar material to be completely ejected from its surface. This is called a Coronal Mass Ejection or CME. (It's complicated why CME's occur, but basically the sun is an ionized gas, so the moving charged particles in the gas feel a magnetic force from the sun's field.) Solar material has a density of about 3 times 10^-4 kg/m^3, and the amount of matter released in a typical CME is around 1 times 10^15 kg. Assuming mu for solar material is mu_0, estimate the strength of the magnetic field at the sun's surface during a typical CME.

Answer 1

magnetic field energy density is given by

energy 1 B2 ,-volume 2 μ По-

total volume of mass released=mass/density=3.333*10^18 m^3

total energy=0.5 *B^2*volume/uo=0.5*m*v^2

solving this we get B=11.64 T