Which equation represents the moment in weight and balance calculations?

• A. Moment divided by Weight
• B. Weight x Arm = Moment
• C. Weight + Arm = Moment
• D. Moment - Weight = Arm

Answer: (B)

Moment is the turning effect produced by a weight located at a certain distance from a reference point. In weight and balance, you determine this turning effect by multiplying the weight (in pounds) by its arm (the distance in feet from the chosen datum). The product, measured in pound-feet, represents the moment.

That’s why the equation Weight x Arm = Moment is the correct representation. The other forms don’t reflect how moments are formed: dividing moment by weight would give the arm, adding weight and arm isn’t a valid way to compute a turning effect, and subtracting weight from a moment isn’t how moments are used in balance calculations. In practice, you compute each item’s moment this way and sum them to get the total moment, then divide by the total weight to find the center of gravity.