Which statement correctly describes the relationship between foot-pounds and inch-pounds?

• A. One foot-pound equals twelve inch-pounds
• B. One foot-pound equals six inch-pounds
• C. One foot-pound equals twenty-four inch-pounds
• D. One foot-pound equals one inch-pound

Answer: (A)

Torque is force times distance, so converting between inch-pounds and foot-pounds uses the length relationship: 1 foot equals 12 inches. That means 1 ft-lb is the same as 12 in-lb. So the statement that one foot-pound equals twelve inch-pounds is the correct description of their relationship. The other options would imply incorrect length conversions (for example, treating a foot as six inches, twenty-four inches, or as if inch-pounds were the same as foot-pounds), which isn’t the actual factor between these units. In short, multiply by 12 to convert foot-pounds to inch-pounds, and divide by 12 to go the other way.