Conservation laws of angular momentum

The conservation law of angular momentum (Equation 12.23) is also reduced to... 

As gas is injected vertically upward into a still water bath, the initial angular momentum of liquid in the bath is zero. If a bubbling jet rotates, for example, counter clockwise, the water and silicone oil outside the bubbling jet rotate clockwise in order to satisfy the conservation law of angular momentum [35,37]. 

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