University Physics Volume 2

Key Equations

Key Equations

 Coulomb’s law $F→12(r)=14πε0q1q2r122r^12F→12(r)=14πε0q1q2r122r^12$ Superposition of electric forces $F→(r)=14πε0Q∑i=1Nqiri2r^iF→(r)=14πε0Q∑i=1Nqiri2r^i$ Electric force due to an electric field $F→=QE→F→=QE→$ Electric field at point P $E→(P)≡14πε0∑i=1Nqiri2r^iE→(P)≡14πε0∑i=1Nqiri2r^i$ Field of an infinite wire $E→(z)=14πε02λzk^E→(z)=14πε02λzk^$ Field of an infinite plane $E→=σ2ε0k^E→=σ2ε0k^$ Dipole moment $p→≡qd→p→≡qd→$ Torque on dipole in external E-field $τ→=p→×E→τ→=p→×E→$