Hypothetically, if you turn on the washing machine without adding detergent after finishing washing your clothes, it is not necessarily the same as doing another rinse cycle. The outcome depends on the specific settings and type of washing machine you have.
Standard Washing Machine: In a standard washing machine, if you turn it on without adding detergent, it will simply run a cycle with water but without any cleaning agents. This will not be the same as doing another rinse cycle because the primary purpose of a rinse cycle is to remove any remaining detergent or soap from the clothes after the main wash. Without detergent, there won't be anything to rinse off.
Modern Washing Machine with Auto-Sensing: Some modern washing machines are equipped with sensors that can detect the level of dirtiness in the water. If you run such a washing machine without adding detergent, it might still detect the absence of soap and may either skip the wash cycle altogether (since there's nothing to clean) or run a much shorter and gentler cycle with water only. These machines are designed to be more efficient and use water and energy based on the load's actual cleanliness.
Specialized Rinse Cycle: Certain washing machines have a specific rinse cycle option that allows you to rinse clothes without an additional wash. If you select this option, the machine will go through a rinse cycle, using water only, to remove any remaining detergent from the clothes.
If you want to ensure your clothes are properly cleaned and rinsed, it's always best to add detergent during the wash cycle. However, if you accidentally forgot to add detergent, it's a good idea to rewash the clothes with detergent to make sure they are properly cleaned. Simply running a cycle without detergent may not achieve the desired level of cleanliness.