Two charged dust particles exert a force of 9.0 ✕ 10-2 n on each other. what will be the force if they are moved so they are only one-ninth as far apart?

The new force would be F' = 7.29x10 N

Explanation: We know that the force between the charges is:

9.0x10^-2 N

Now, the force between two charged particles can be obtained by the Coulomb's law:

F = k*q1*q2/r^2

where k is a constant, q1 and q2 are the charges of the particles and r is the distance between the particles.

then we have that:

k*q1*q2/r^2 = 9.0x10^-2 N

if we move tha particles only one ninth as far apart, then we have a new force:

F´= k*q1*q2/(r/9)^2 = 181k*q1*q2/r^2 = 81*F = 81*9.0x10^-2 N = 729x10^-2

F' = 7.29x10 N

the device is called “ rocket engine”

it takes about 30 days for it to break down