Final answer:
The compound unit equivalent to a watt times a second is a Joule.
Step-by-step explanation:
The compound unit that is equivalent to a watt times a second is a Joule (A).
A watt (W) is a unit of power, defined as one joule per second (1 J/s). Therefore, when you multiply a watt by a second, you get a unit of energy, which is the Joule (J).
For example, if you have a 100-watt light bulb that is turned on for 10 seconds, the total energy consumed would be 100 watts * 10 seconds = 1000 joules.