One watt is equivalent to which of the following?

One watt is defined as the rate of energy transfer equivalent to one joule per second. This means that if you have a device operating with a power output of one watt, it is consuming or converting energy at the rate of one joule every second. This definition stems from the relationship between power, which measures how quickly work is done or energy is transferred, and energy itself.

In practical terms, understanding this connection is crucial for applications such as calculating energy consumption in electrical devices, where knowing the power rating in watts allows for estimation of energy use over time. Therefore, when considering the choices, the definition of wattage aligns perfectly with this concept, confirming that one watt indeed corresponds to one joule per second.