Question

Suppose the exact charge neutrality does not hold in a world and the electron has a charge $1\%$ less in magnitude than the proton. Calculate the Coulomb force acting between two blocks of iron each of mass $1kg$ separated by a distance of $1m$. The number of protons in an iron atom$=26$ and $58kg$ of iron contains $6\times {10}^{26}$ atoms.

Answer 1

Given two blocks of iron each of mass $1Kg$ separated by a distance $1m$. Number of protons in iron atom $=26$

$58Kg$ of iron contains $6\times {10}^{26}$ atoms

We have to find Coulomb's Force between two iron blocks.

Also given, electron has a charge $1$ less than proton. Since each atom of iron will have a net positive charge $26\times 0.01\times 1.6\times {10}^{-19}C$ on it.

Total positive charge on $1Kg$ block would be $\frac{6\times {10}^{26}\times 26\times 1.6\times {10}^{-21}}{58}$

$=4.3\times {10}^{5}C$

So, the coulomb force between two blocks is

$F=\frac{1}{4\pi {\epsilon }_0}\frac{q_1{q}_2}{r^2}$

$=\frac{9\times {10}^9\times (4.3\times {10}^5{)}^2}{(1m{)}^2}$

$=1.7\times {10}^{-21}N$