5 free precision ag calculators and tools. Solve real-world precision ag problems instantly with accurate, step-by-step results on ApexCalc.
| Constant | Symbol | Value |
|---|---|---|
| Speed of light | c | 2.99792458×10⁸ |
| Planck's constant | h | 6.62607015×10⁻³‴ |
| Boltzmann constant | kʙ | 1.380649×10⁻²³ |
| Avogadro's number | Nₐ | 6.02214076×10²³ |
| Gravitational constant | G | 6.6743×10⁻¹¹ |
| Gas constant | R | 8.31446 |
| Elementary charge | e | 1.602176634×10⁻¹⁹ |
| Electron mass | mₑ | 9.1093837015×10⁻³¹ |
| Proton mass | mₚ | 1.67262192369×10⁻²⁷ |
| Fine-structure constant | α | 7.2973525693×10⁻³ |
Calculate soil nitrogen, phosphorus, and potassium balance from soil test results, yield goals, and crop removal rates.
Convert fertilizer nutrient requirements to product application rates for common fertilizers (urea, DAP, MAP, potash). Calculate blended fertilizer ratios.
Schedule irrigation using the soil water balance method. Calculate evapotranspiration, allowable depletion, and irrigation intervals from FAO-56 Penman-Monteith ET₀.
Calculate crop evapotranspiration (ETc) from reference ET and crop coefficients (Kc) for major crops across growth stages.
Quantify the yield gap between potential (climate-limited), attainable (water-limited), and actual farm yields. Identify limiting factors.