Home/Basic Physics/Basic electricity/Kirchhoff's first law16. Basic electricityKirchhoff's first lawIn 16. Basic electricityFormulaCopy LaTeX∑Ientra=∑Isale\sum I_{\text{entra}}=\sum I_{\text{sale}}∑Ientra=∑IsaleEquivalentlyCopy LaTeX∑I=0\sum I=0∑I=0Tagselectricityelectricity basicphysicsphysics formulaDetailAt a node, the sum of currents entering equals the sum of currents leaving.Explore the ideaExplore the ideaFound an error? Contact us.Related formulasRelatedElectric currentI=ΔQΔtI=\frac{\Delta Q}{\Delta t}I=ΔtΔQOpen formulaOpen in sectionRelatedKirchhoff's second law∑ΔV=0\sum\Delta V=0∑ΔV=0Open formulaOpen in sectionRelatedNodal analysis with KCL∑kVn−VkRnk=In\sum_k\frac{V_n-V_k}{R_{nk}}=I_nk∑RnkVn−Vk=InOpen formulaOpen in section