If a negative charged particle enters a magnetic field perpendicularly,then it follows a circular path.In what directn does the particle move---in clockwise or anticlockwise?
Solution) If field is above paper then it make a anticockwise circle
if field is into then it makes a clockwise circle
by using flemings left hand rule we can find the direction of centripetal force and can find trajectory for a positive charga.for negative charge take the opposite direction to positive one