pound foot/square second (lb·ft/s²) to ton-force (long) (tonf (UK))

pound foot/square second (lb·ft/s²) to ton-force (long) (tonf (UK)) conversion guide

pound foot/square second (lb·ft/s²) to ton-force (long) (tonf (UK)) expresses the same force in a different unit. The direction matters: a value given in pound foot/square second (lb·ft/s²) is multiplied by the source-to-target factor to obtain ton-force (long) (tonf (UK)). Keep the original measurement and its unit together when copying a result into a calculation.

Conversion formula

Value in ton-force (long) (tonf (UK)) = value in pound foot/square second (lb·ft/s²) × (381 / 27458620). The factor is approximately 0.00001387542418. Derive it by dividing the source unit value in the base unit by the destination unit value in the same base unit.

About these units

pound foot/square second (lb·ft/s²): One poundal is one international avoirdupois pound foot per second squared, equal to 0.138254954376 newtons. It differs from pound-force and does not use standard gravity in its definition. One source unit equals 0.1382549544 newton.

ton-force (long) (tonf (UK)): A force unit, not a mass unit. Gravitational force units here use conventional standard gravity of 9.80665 meters per second squared. One destination unit equals 9964.016418 newton.

Worked examples

• 1 pound foot/square second (lb·ft/s²) = approximately 0.00001387542418 ton-force (long) (tonf (UK))
• 2.5 pound foot/square second (lb·ft/s²) = approximately 0.00003468856046 ton-force (long) (tonf (UK))
• 10 pound foot/square second (lb·ft/s²) = approximately 0.0001387542418 ton-force (long) (tonf (UK))

Precision and interpretation

Examples are rounded for display. Keep the unrounded factor for intermediate calculations and round the final answer to match the precision of the original measurement. Extra decimal places do not make a measured quantity more accurate.

Force and mass are different quantities. Check the distinction between pound-force and pound mass, and between metric, short, and long ton-force.

Common questions

How do I reverse this conversion?

Divide the target-unit value by the forward factor, or use the inverse converter. Multiplying by the same factor again is not the inverse operation.

Why can the displayed answer differ slightly?

Display rounding and numerical precision can produce a small difference from an exact fractional calculation. For technical work, retain sufficient precision and confirm the unit convention required by the source.

Related conversions

Force unit converters, Mass and weight converters, Everyday unit converters.