Question Number 39622 by NECx last updated on 08/Jul/18
$${Two}\:{charges}\:{Q}_{\mathrm{0}} \:{and}\:\mathrm{3}{Q}_{\mathrm{0}} \:{are}\:{at}\:{l} \\ $$$${distance}\:{apart}.{These}\:{two}\:{charges} \\ $$$${are}\:{free}\:{to}\:{move}\:{but}\:{do}\:{not}\:{because} \\ $$$${is}\:{a}\:{third}\:{charge}\:{nearby}.{What}\:{must} \\ $$$${be}\:{the}\:{charge}\:{for}\:{the}\:{first}\:{two}\:{to}\:{be} \\ $$$${in}\:{equilibrium}? \\ $$