Answer to Question #165291 in Electricity and Magnetism for Nuel Fudalan

Question

A small sphere of charge q₁ = +8.00 x 10^-5 C is at a distance r = 2.67 m from another small sphere of charge q₂ = -6.00 x 10^-5 C (a) What is the magnitude of the attractive electric force between these two charged spheres? (b) How many excess protons are there in the small sphere with charge q₁ ? (c) How many excess electrons are there in the small sphere with charge q₂ ?

Answer 1

Answer

(a)

Attractive force

$F=k\frac{q_1q_2}{r^2}$

$F=(9\times10^9)\frac{(8.0\times10^{-5})(6.0\times10^{-5})}{2.67^2}$

$F=6N$

(B)

Number of proton on small sphere

$q_1=n_1e\\n_1=\frac{q_1}{e}=\frac{8.00\times10^{-5}}{1.6\times10^{-19}}=5\times10^{14}$

(C)

Excess of electron on sphere

$q_2=n_2e\\n_1=\frac{q_1}{e}=\frac{6.00\times10^{-5}}{1.6\times10^{-19}}=3.75\times10^{14}$