Final answer:
When stirring water, work is done on the system, increasing its internal energy and resulting in a temperature increase.
Step-by-step explanation:
True. When stirring water, work is done on the system, which increases its internal energy. This increase in internal energy leads to an increase in temperature. One example of this is when you stir a pot of cold water on a stove, the water heats up as a result of the work done by stirring.