What is the standard SI unit for power?

The standard SI unit for power is the Watt. Power is defined as the rate at which work is done or energy is transferred over time. In terms of units, one Watt is defined as one Joule per second. This relationship illustrates that the Watt is quantifying how much energy is being used or converted per unit of time.

When discussing the other options: a Joule measures energy, a Newton measures force, and a Pascal measures pressure. While all of these are crucial concepts in physics and chemistry, they measure different physical quantities and are not used to express power. Therefore, the Watt is the only appropriate unit among the choices provided for measuring power.