Question

Em cima do eixos das ansiosas (x) ficamos dois corpusculos eletrizados A e B com carga Qa=9mc e Qb=16m determine a abscissas de um ponto "p" no qual o campo elétrico resultante e nulo A.____.P________.B__> Xa=0cm Xb=7 cm

Answer 1

$Q_A=4\ mC=4\times10^{-3}\ C;\ Q_B=16\ mC=16\times10^{-3}\ C\\\\ \vec{E}_A+\vec{E}_B=0\ \to\ \vec{E}_A=-\vec{E}_B\ \to\ |\vec{E}_A|=|\vec{E}_B|\ \to\\\\ \to\ \dfrac{K_0|Q_A|}{d_{AP}^2}=\dfrac{K_0|Q_B|}{d_{BP}^2}\ \to\ \dfrac{9\times10^{-3}}{d_{AP}^2}=\dfrac{16\times10^{-3}}{d_{BP}^2}\ \to\\\\ \to\ 9d_{BP}^2=16d_{AP}^2\ \to\ 3d_{BP}=4d_{AP}\ \to\ d_{BP}=\dfrac{4}{3}d_{AP}\\\\ d_{AP}+d_{BP}=9\ \to\ d_{AP}+\dfrac{4}{3}d_{AP}=9\ \to\ \dfrac{7}{3}d_{AP}=9\ \to\\\\ \to\ d_{AP}=\dfrac{27}{7}\ \to\ x_P-x_A=\dfrac{27}{7}\ \to\ x_P=\dfrac{27}{7}\\\\ \boxed{P=\bigg(\dfrac{27}{7},0\bigg)}$