Give the magnitude and direction of the net force acting on
(a) ZERO, since it's moving with constant speed, and downward, and direction is also not changing.
(b)ZERO, since it's floating on water surface and weight is balanced by buoyancy force.
(c)ZERO, since it's held stationary, so net force acting on it is zero.
(d)ZERO, since constant velocity means zero acceleration and hence zero net force.
(e)ZERO, since electron will experience only electromagnetic force, and it's given that the region is free of electric and magnetic fields.
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