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Two unlike charges separated by a distance of 1m attract each other with a force 0.108N. If the charges are in the ratio 1:3, the weak charge is?A. 2 micro C ,B. 4 micro C, C. 6 micro C, D. 5 microC
Here q1:q2=1:3,
3q1=q2,
we know F=k(q1q2)/(r2)
where k=9x109N-m2/C2
thus 0.108=9x109(3(q2)2)/12
q2=2x10-6C
therefore the weak charge is 2micro C.
i think it is 2 microC
let charges be x,3x;
f=3x*x*9*10^9 =>x= 2 micro
The answer is 4 micro C. But it could be wrong.