If you run around a circular track with a radius of 10m, what is the displacement after 3 full laps back to the start line?

The magnets are probably damaged or there not strong enough to attached to the refrigerator

An atom's smaller negative particles are at a distance from the central positive particles, so the negative particles are easier to move. 

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Answerthe force between the charges will be  f/9 (one-ninth of force f)explanationcoulomb's law relates the magnitudes  two point charges q₁ and q₂, the distance, r, between the charges, and the electrostatic force, f, between the two charges:     k represents coulomb's constant, k = 8.99×10⁹ n·m²/c².note that if we have r = 3r, then