formulate calculation in electricity voltage volt U U = R.I intensity amps I I = U ⁄ R resistance ohm R R = U ⁄ I quantity amps ⁄ h Q Q = I.t intensity amps A I = Q ⁄ t time Se ou Mi ou He t t = Q ⁄ I resistance ohm R R = (p.l) ⁄ S section mm² S S=(p.l) ⁄ R resistivity omh ⁄ m ⁄ mm² p p=(R.S) ⁄ l lengt meter m l=(R.S) ⁄ p resistance at t° ohm ⁄ t° Rt° Rt = R0.(1 + a.t) section mm² S S = (3.1415.d²) ⁄ 4 section mm² S S = (r.r.3.1415) density A ⁄ mm² J J = I ⁄ S equivalente resistance in serie ohm Re Re = R1 + R2 + Retc equivalente resistance on ⁄⁄ ohm Re 1 sur Re = 1 sur R1 + 1 sur R2 etc wheatstone R1 sur R2 = R4 sur R3 potenciel newton N 1 Kg = 9.81 N work joule J 1 J = 1 N.1M power watt P P = W ⁄ t power watt P U.Q power watt P U.I.t single phase power watt P U.I.CosPhi three phase power triangle watt P U.(I.1,7320).CosPhi three phase power star watt P (U.1,7320).I.CosPhi performance % n(éta) n = Pu ⁄ Pa heat joule Q Q = R.I².t resistance ohm R R = Q:(I².t) specific heat joule C Q = M.t°.C voltage of a battery volt E E = U+u intensity amps I I = E ⁄ (R+r) capacity amps/hour Q Q = I.t intensity amps I I = Q ⁄ t time Se ou Mi ou He t t = Q ⁄ I intensity accumulator amps A I = (U-E) ⁄ (R+r) fcem volt E E = U-I.(R + r) internal battery resistance ohm r r = ]U-E-(R.I)_ ⁄ I magnetic field intensity amps ⁄ meter H H = I ⁄ D transformation ratio coéfficient K K = Up ⁄ Us conductance S(siemens) siemens G G = 1 ⁄ R conductivity S (siemens) siemens Y Y = 1 ⁄ p capacity reactance Xc Xc Xc = 1 ⁄ (2*PI*f*C) power factor Cos phi Cos phi Cos phi = p ⁄ (u*i) or p ⁄ s compensation capacitor Qc Qc Qc = 3*u²*c*w relation between current ⁄ charge Ic Ic Ic(t) = dq*(t) ⁄ dt relation charge ⁄ potencial difference Q(t) Q(t) Q(t) = C*]Vc*(t)_ relation charge ⁄ potencial difference Ic(t) Ic(t) Ic(t) = C*(dvc*t) ⁄ dt equation breaking capacity,short circuit L*(di ⁄ dt) = Er-Uarc-(R*I) wind power wind turbine blade betz limit P vent P vent = (1 ⁄ 2).p.S.v³ power of the wind turbine betz limit P rotor P rotor = (1 ⁄ 2).cp.p.S.v³ power supplied by wind turbine Power Kw P = k * s * v² Steinmetz formula Hysteresis loss w w = k * V * F * Bnm

execution time customer :
runtime server : 0.006 seconds