Question

) A intensidade do campo elétrico, num ponto situado a 3,0 mm de uma carga elétrica puntiforme Q = 2,7x10⁻⁶C no vácuo (ko = 9x10⁹ N.m²/C²) é: *
a) 2,7x10³ N/C
b) 8,1x10³ N/C
c) 2,7x10⁶ N/C
d) 8,1x10⁶ N/C
e) 2,7x10⁹ N/C​

Answer 1

$\mathrm{Dados}\Longrightarrow d=3\ \text{mm}=3\times10^{-3}\ \text{m};\ Q=2.7\times10^{-6}\ \text{C}.$

$\boxed{|\vec{E}|=\dfrac{k_0|Q|}{d^2}}\Longrightarrow |\vec{E}|=\dfrac{9\times10^9|2.7\times10^{-6}|}{(3\times10^{-3})^2}$

$\Longrightarrow |\vec{E}|=\dfrac{24.3\times10^3}{9\times10^{-6}}\ \therefore\ \boxed{|\vec{E}|=2.7\times10^9\ \mathrm{N/C}}$