What is the longest the bolt can be and still be acceptable
I think it’s d because it talks about a spring with is common like the spring in a pen
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
That is right because base*length is how you get the height
Answer:
2×10^-4m^3/0.002m^3
Explanation:
first know the formula of getting density which is
density=mass/volume
substitute with values given in the problem
{before beginning convert all the values to SI units}
13600m/cm^3=2.27kg/x
calculate to solve for x=volume