Power is measured in which unit?

• A. $\frac{m}{s}$ (meters per second)
• B. $J$ (joules)
• C. $W$ (watts)
• D. $\frac{N}{m}$ (newtons per meter)

Answer: (C)

Verified step by step guidance

1. Understand that power in physics is defined as the rate at which work is done or energy is transferred over time.
2. Recall that work or energy is measured in joules (J), and time is measured in seconds (s).
3. Therefore, power is calculated as energy divided by time, which can be expressed as \(P = \frac{E}{t}\), where \(P\) is power, \(E\) is energy in joules, and \(t\) is time in seconds.
4. The SI unit for power is the watt (W), which is equivalent to one joule per second, or \$1\ \text{W} = 1\ \frac{J}{s}$.
5. Recognize that other units given, such as meters per second (m/s), joules (J), and newtons per meter (N/m), do not represent power but rather speed, energy, and force per distance respectively.