# Ten positively charged particles are kept fixed on the X-axis

Question:

Ten positively charged particles are kept fixed on the X-axis at point $x=10 \mathrm{~cm}, 20 \mathrm{~cm}, 30 \mathrm{~cm}, \ldots ., 100 \mathrm{~cm}$. The first particles have a charge $1.0^{\times 10^{-6}} \mathrm{C}$, the second $8^{\times 10^{-8}}$, and the third $27^{\times 10^{-8}} \mathrm{C}$ and so on. The tenth particle has a charge $1000^{\times 10^{-8}}$ C. Find the magnitude of the electric force acting on a $1 \mathrm{C}$ charge placed at the origin.

Solution: