A stone is tied to the end of a string. When the string is whirled in a circular path, the string can never be kept horizontal. Explain the reason.

A stone is tied to the end of a string. When the string is whirled in

1.	A stone is tied to the end of a string. When the string is whirled in a circular path, the string can never be kept horizontal. Explain the reason.
Answer» Solution :When astone tied to the end of a string is whirled along a HORIZONTAL circular path, the horizontal component of the tension in the string provides the necessary centripetal force and its vertical component balances the weight of the STONE. If the stone is rotated along a horizontal circular path by keeping the string horizontal, there would be no vertical component of the tension (T) in the string. In that case, the weight of the body (mg) cannot be balanced. As a result, the stone would DIP downwards leaving the horizontal circular path until the vertical component of T would be just sufficient to balance the weight of the stone. Hence, during ROTATION of the stone along a horizontal circular path, the string can NEVER be kept horizontal.