A charged particle is whirled in a horizontal circle on a frictionless table by attaching it to a string fixed at one point. If a magnetic field is switched on in the vertical direction, how will it affect the tension in the string ?

will increase will decrease will remain the same may increase or decrease

may increase or decrease

If the particle experiences a force outward in the direction of the radius, tension T will increase. If the particle experiences a force inward in the direction of the radius towards the center, tension T will decrease.