Which of the following best describes what one $W$ is equal to?

• A. $1J\cdot s$
• B. $1\mathrm{kg}\cdot m{s}^{-}$
• C. $1V\cdot A$
• D. $1J/s$

Answer: (D)

Verified step by step guidance

1. Recall the definition of a Watt (W): it is the SI unit of power, which measures the rate of doing work or transferring energy.
2. Express power in terms of energy and time: Power = Energy / Time, so 1 Watt = 1 Joule per second, or \$1\,W = \frac{1\,J}{1\,s}$.
3. Consider the other given options and analyze their units: 1 Joule times second (\$1\,J \cdot s$) is energy multiplied by time, which does not represent power.
4. 1 kilogram times meter per second squared (\$1\,kg \cdot m \cdot s^{-2}$) corresponds to a unit of force (Newton), not power.
5. 1 Volt times Ampere (\$1\,V \cdot A\() is also a unit of power, since electrical power is voltage times current, which is equivalent to Watts; however, the problem states the correct answer is \)1\,J/s$, emphasizing the fundamental definition of Watt.