The force of attraction between 2 charged spheres can be explained by Coulomb's law,
It states the force of attraction is directly proportional to the magnitudes of the charges and inversely proportional to the square of the distance between the charges.
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where F - force of attraction/repulsion
q₁ and q₂ - charges of the 2 spheres
k - Coulomb's law constant
r - distance between the spheres
In the question given, the charges of the spheres remain constant in both instances, only distance changes. Therefore (kq₁q₂) = c which is a constant
then F = c / r²
first instance
6 x 10⁻⁹ N = c/ (20 cm)² ---1)
F = c/(10 cm)² --- 2)
2) / 1)

F = 6 x 10⁻⁹ x 4
F = 2.4 x 10⁻⁸ N
I believe the correct answer from the choices listed above is the last option. The advances in food production that were attributed to the Green Revolution of the 1960s and 1970s are drought-resistant varieties of crop plants.
Hope this answers the question. Have a nice day.
Answer: 4.19 N
Explanation: In order to determinate the tension applied on the wire we have to calculate the electric force between the conductor spheres connected by the wire.
As the wire is a conductor the spheres are at same potential so we have:
V1=V2
V1=k*Q1/r1 and V2=k*Q2/r2
where r1=r2, then
Q1=Q2
so the electric force is given by:
F=k*Q^2/d^2 where d is the distance between the spheres.
Finally replacing the values, we have
F=9*10^9(41*10^-6)^2/(1.9)^2= 4.19 N
10 is the number that is subtracted from it is the MINUEND
4 is the number being subtracted its then the SUBTRAHEND
6 is the result it is then the DIFFERENCE
so the correct term for 4 is SUBTRAHEND