Question Number 39573 by NECx last updated on 08/Jul/18
$${Point}\:{charges}\:\mathrm{88}\mu{C},−\mathrm{55}\mu{C}\:{and} \\ $$$$\mathrm{70}\mu{C}\:{are}\:{placed}\:{in}\:{a}\:{straight}\:{line}. \\ $$$${The}\:{central}\:{one}\:{is}\:\mathrm{0}.\mathrm{75}{m}\:{from} \\ $$$${each}\:{of}\:{the}\:{others}.{Calculate}\:{the} \\ $$$${net}\:{force}\:{on}\:{each}\:{due}\:{to}\:{the}\:{other} \\ $$$${two}. \\ $$
Commented by NECx last updated on 08/Jul/18
$${Please}\:{give}\:{a}\:{diagram}\:{if}\:{necessary}. \\ $$$${Thanks}\:{in}\:{advance}. \\ $$$$ \\ $$
Answered by tanmay.chaudhury50@gmail.com last updated on 08/Jul/18
$$\left({F}\right)_{−\mathrm{55}} ^{\mathrm{88}} =\mathrm{9}×\mathrm{10}^{\mathrm{9}} ×\frac{\mathrm{88}×\mathrm{10}^{−\mathrm{6}} ×\left(−\mathrm{55}\right)×\mathrm{10}^{−\mathrm{6}} }{\left(^{} \mathrm{0}.\mathrm{75}\right)^{\mathrm{2}} }\:{forc}\:{on} \\ $$$${Q}=\mathrm{88}\mu{C}\:{by}\:\left(−\mathrm{55}\mu{C}\right)\:\:{attractive} \\ $$$$\left({F}\right)_{\mathrm{77}} ^{\mathrm{88}} =\mathrm{9}×\mathrm{10}^{\mathrm{9}} ×\frac{\mathrm{88}×\mathrm{10}^{−\mathrm{6}} ×\mathrm{70}×\mathrm{10}^{−\mathrm{6}} }{\left(\mathrm{1}.\mathrm{5}\right)^{\mathrm{2}} }\:\:\:{repulsi} \\ $$$${so}\:{net}\:{firce}\:{on}\:\mathrm{88}{C}\:{by}\:{othdrs}\:{two}\:{charge}\:{is} \\ $$$$\left({F}\right)_{−\mathrm{55}} ^{\mathrm{88}} \sim\left({F}\right)_{\mathrm{70}} ^{\mathrm{88}} \:\:{similar}\:{way}\:{other}\:{can}\:{be}\:{calculated} \\ $$$$ \\ $$
Commented by NECx last updated on 08/Jul/18
$${But}\:{the}\:{textbook}\:{says}\:\mathrm{53}{N},\mathrm{16}{N}\:{and} \\ $$$$\mathrm{37}.....{Please}\:{can}\:{you}\:{enlighten}\:{me} \\ $$$${on}\:{how}\:{they}\:{came}\:{about}\:{these}\:{results}. \\ $$