        MyCTMainForum  Newton's gravitation law

Astronomy, astrophysics index               The inverse-square law of Newton's law of universal gravitation is used to calculate the attractive force acting on bodies, and their potential energy.              Mass 1 kg --- METRIC --- ng µg mg grams tonnes M tonnes -- IMPERIAL -- grains ounces pounds stones cwt tons --- OTHER --- u (Da) Troy ounces carats pennyweight Moons Earths Suns Mass 2 kg --- METRIC --- ng µg mg grams tonnes M tonnes -- IMPERIAL -- grains ounces pounds stones cwt tons --- OTHER --- u (Da) Troy ounces carats pennyweight Moons Earths Suns Separation m --- METRIC --- pm nm microns (µm) mm cm km -- IMPERIAL -- mil 1/16 inch inches feet yards miles - SCIENTIFIC - Planck Bohrs Angstrom light-seconds light-years au parsecs --- OTHER --- points cubits fathoms rods chains football fields furlongs Roman miles nautical miles leagues Gravitational force N (kg⋅m/s²) - SI UNITS - µN mN kN MN --- OTHER --- atomic unit dyne pdl lbf kg-force ton-force Potential energy J - SI UNITS - nJ µJ mJ kJ MJ GJ -- IMPERIAL -- cal kcal ft⋅pdf ft⋅pdl BTU - SCIENTIFIC - eV keV Hartrees (au) kJ/mol wavenumber kHz photon MHz photon GHz photon THz photon nm photon nm mole of ph. --- OTHER --- erg kWh barrels of oil tons of coal tons of TNT ktons of TNT Mtons of TNT Krakatoas   To calculate the potential energy gained or lost upon a distance change, the potential energy at the two distances must both be calculated and then one subtracted from the other. Note that the potential energy is always negative, because it is defined as 0 at an infinite separation.          