A stone is tied to s string and whirled around in a circle at constant speed. Is the string more likely to break when the circle is horizontal or when it is vertical? Account for your answer, assuming the constant speed is the same.

Vertical

Explanation:

When the circle is horizontal, the tension in the string is equal to the centripetal force. When the circle is vertical, the tension is greater since it is equal to the centripetal force plus the weight of the stone. Therefore, the string is more likely to break when the circle is vertical