The aurora is caused when electrons and protons, moving in the earth's magnetic field of ≈5.0×10−5t, collide with molecules of the atmosphere and cause them to glow. part a what is the radius of the circular orbit for an electron with speed 3.0×106 m/s ? assume that the electron moves in a plane perpendicular to the magnetic field.

Explanation:

The circular movement is produced by the magnetic field:

This force is a centripetal force because the electron moves in a plane perpendicular to the magnetic field. For a centripetal Force, that produces a circular orbit with a radius r:

If we solve these two equations in order to find r, with the mass and charge of a electron:

when jerome paddle in flowing river towards east the net speed of jerome will increase

so the net speed of jerome will be given as

now the speed of paul will be same as it is given as he is running on the ground

so

so here we can say since the speed of jerome is more so he will win the race

now as we know the distance so the time difference is given as

so jerome will reach first and the time difference will be 203.55 s or 3.4 min