Question

the concept of energy can be calculated in multiple ways. which units are used for energy? check all that apply. joules kilogram meters²/seconds² newtons kilojoules meters/seconds²

Explanation:

• Joules: The SI unit of energy is the joule (J).
• Kilogram meters²/seconds²: From the formula for work (and energy, since work is a form of energy) \( W = Fd \), and force \( F = ma \) (mass \( m \) in kg, acceleration \( a \) in \( \text{m/s}^2 \)), so work (energy) has units \( \text{kg} \times \text{m/s}^2 \times \text{m}=\text{kg}\cdot\text{m}^2/\text{s}^2 \), which is equivalent to a joule.
• Kilojoules: A kilojoule (kJ) is \( 1000 \) joules, so it is also a unit of energy.
• Newtons: Newtons (N) are units of force (\( \text{kg}\cdot\text{m/s}^2 \)), not energy.
• Meters/seconds²: This is the unit of acceleration, not energy.

Answer:

A. joules, B. kilogram meters²/seconds², D. kilojoules