Magnets are attached to a falling object, which is allowed to fall through a conducting ring. A magnetic impulsive force produced by the ring reduces (very slightly) the velocity of the object. The impulsive force is fully characterized using a novel method for measuring the velocity and acceleration of the object, which allows for determination of the gravitational field strength, to within 0.2% of the published local value. The experimentally obtained impulsive force is well explained by the calculated Lorentz force acting on the ring.
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