Question

Three point charges of magnitude $5 \,\mu C$, $0.16 \,\mu C$ and $0.3 \,\mu C$ are located at the vertices A, B, C of a right angled triangle whose sides are $A B=3 \,cm , B C=3 \sqrt{2} \,cm$ and $CA =3 \,cm$ and point $A$ is the right angle corner. Charge at point A experiences _______$N$ of electrostatic force due to the other two charges.

Answer 1

$ F _1=\frac{ k \times 5 \times 0.3 \times 10^{-12}}{9 \times 10^{-4}} $
$=\frac{9 \times 10^9 \times 5 \times 0.3 \times 10^{-12}}{9 \times 10^{-4}} $
$ =1.5 \times 10=15 N $
$F _2=\frac{9 \times 10^9 \times 5 \times 0.16 \times 10^{-12}}{9 \times 10^{-4}}=8 N$
force experienced by charge at
$A =\sqrt{ F _1^2+ F _2^2} $
$=\sqrt{15^2+8^2} $
$ =\sqrt{289}=17 N$