At what condition does a body become weightless at the equator?

A body become weightless at the equator if force of gravity and centrifugal force of the earth become equal.

When the centrifugal force is equal to the gravitational force of the body in that condition the body experiences weightlessness at the equator. The weight of the body is due to the higher gravitational force of the earth than its centrifugal force so if both forces are equal to each other than the weight becomes zero.

If the earth start to spin faster about 17 times, then the centrifugal force would become equal to the gravitational force and an object would experience weightlessness so we can conclude that a body become weightless at the equator if force of gravity and centrifugal force of the earth become equal.

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force required to detach it is given by

charges are taken to be fundamental charge

now we have

so above is the minimum distance at which it will detach