A watt is a unit of power, specifically it is one joule of energy per second. It is named after James Watt, the inventor of the steam engine. What is a watt in electricity? A watt is a unit of power in the International System of Units (SI). It is defined as 1 joule per second and is used to quantify the rate of energy transfer. What is watt and ampere? Watt and ampere are units of measurement for electrical power and current, respectively. One watt is equal to one joule of energy per second, and one ampere is equal to one coulomb of charge per second. What is watt and Volt? Watt and volt are two basic units used to measure electrical power and potential, respectively. One watt is equal to one joule of energy per second, while one volt is equal to one joule of energy per coulomb of charge. What does 1 watt-hour mean? 1 watt-hour is a unit of energy, and it refers to the amount of energy that is required to produce one watt of power for one hour. So, for example, if you have a 100-watt light bulb and you want to run it for 10 hours, you would need 1,000 watt-hours of energy. How many volts is 300 watts? 300 watts is equal to 300 volts.