Convert Calories per Gram to Foot-Pounds per Pound

The Calorie per Gram (symbol: cal/g) is a unit of specific energy. A CGS specific-energy unit equal to exactly 4,184 J/kg (using the thermochemical calorie definition per NIST SP 811), numerically identical to kcal/kg. cal/g is the working unit for chemistry reaction enthalpies per unit mass (heats of combustion measured in bomb calorimeters per ASTM D240 / D5865), food science nutritional energy (1 dietary 'Calorie' = 1 kcal = 1,000 cal — a confusing convention that persists despite ISO 80000-5 deprecation), thermochemistry per the NIST WebBook and Linstrom-Mallard NIST Standard Reference Database 69, and DSC (Differential Scanning Calorimetry) integration output for biological and pharmaceutical samples (TA Instruments, Mettler Toledo, PerkinElmer instruments default to cal/g for some legacy methods). Reference values per Atkins Physical Chemistry: water heat of vaporization at 100°C ≈ 540 cal/g; ice heat of fusion ≈ 80 cal/g; sucrose heat of combustion ≈ 3,940 cal/g; protein heat of combustion ≈ 4,100 cal/g; fats/oils ≈ 9,200 cal/g (the basis of the '9 calories per gram' nutritional rule of thumb for fat). Food labels outside the US showing 'kcal per 100g' display this unit scaled to a 100-gram serving size.

It belongs to the metric measurement system.

Calories per Gram are commonly used in fuel comparison, battery technology, and rocket propulsion.

The Foot-Pound per Pound (symbol: ft·lbf/lb) is a unit of specific energy. An imperial specific-energy unit equal to approximately 2.98907 J/kg (1 ft·lbf = 1.35582 J; 1 lb = 0.45359237 kg; ratio = 2.98907). ft·lbf/lb is a niche US-engineering unit used primarily in: ballistic kinetic-energy-per-mass calculations (E_k/m for projectiles, where US ballistics literature historically uses imperial mass for the projectile and ft·lbf for muzzle energy — a .308 Winchester 168gr bullet at 2,650 fps muzzle velocity has specific energy ~109,000 ft·lbf/lb), US-edition mechanical-engineering textbooks for mechanical strain-energy-per-mass calculations (Shigley, Norton, Hibbeler in dual-unit editions), and head-loss / hydraulic-energy specific calculations in US civil-engineering hydraulics where the natural unit is feet-of-head (1 ft of head of water ≈ 1 ft·lbf/lb specific gravitational potential). For typical engineering specific-energy scales (gasoline, batteries, structural-strain energy), the ft·lbf/lb numerical value is large and unwieldy — gasoline LHV is ~15.5 million ft·lbf/lb — so US engineers usually convert to BTU/lb for fuel work and reserve ft·lbf/lb for kinetic and elastic-strain applications. Convert ft·lbf/lb to J/kg by multiplying by 2.98907.

It belongs to the imperial measurement system.

Foot-Pounds per Pound are commonly used in fuel comparison, battery technology, and rocket propulsion.