What unit is used to measure both work and heat?

What unit is used to measure both work and heat?

• A. Calories
• B. Joules
• C. Watts
• D. Newtons

Answer: (B)

Both work and heat are forms of energy transfer, so they’re measured in the SI unit for energy: the joule. Using joules keeps the measurement consistent in physics. A calorie is another energy unit, often used in nutrition, but not the standard in physics. Watts describe power—energy per time—which isn’t the total energy transferred, and Newtons measure force, not energy. If you ever need a quick check, 1 calorie is about 4.184 joules, but the conventional unit for both work and heat is the joule.

Both work and heat are forms of energy transfer, so they’re measured in the SI unit for energy: the joule. Using joules keeps the measurement consistent in physics. A calorie is another energy unit, often used in nutrition, but not the standard in physics. Watts describe power—energy per time—which isn’t the total energy transferred, and Newtons measure force, not energy. If you ever need a quick check, 1 calorie is about 4.184 joules, but the conventional unit for both work and heat is the joule.