A small ball of mass m and charge q is attached to the bottom end of a piece of negligible mass thread of length l, whose top end is fixed. The system formed by the thread and ball is in vertical plane and is in uniform horizontal magnetic field B, which is perpendicular to the plane of figure and points into the paper The ball is started with a velocity v_(0)from lower most point of circle in a direction perpendicular both to the magnetic induction and to direction of thread. The ball moves along a circular path such that thread remains tight during the whole motion. Neglect any loss of enery. Choose CORRECT statement

A small ball of mass m and charge q is attached to the bottom end of a

1.	A small ball of mass m and charge q is attached to the bottom end of a piece of negligible mass thread of length l, whose top end is fixed. The system formed by the thread and ball is in vertical plane and is in uniform horizontal magnetic field B, which is perpendicular to the plane of figure and points into the paper The ball is started with a velocity v_(0)from lower most point of circle in a direction perpendicular both to the magnetic induction and to direction of thread. The ball moves along a circular path such that thread remains tight during the whole motion. Neglect any loss of enery. Choose CORRECT statement
Answer» If direction of magnetic field is reversed then VALUE of B will be same as calculated in above question of this PARAGRAPH If B is reversed, then conservation of ENERGY will still be applicable If magnetic field were not present then PARTICLE will complete vertical circle for any value of `v_(0)` All of above are correct Answer :B

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