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Mission SE8 Coulomb's Law Equation as a Guide to Thinking

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 The Question

Which of the following would cause the electrical force between two objects to increase (OR decrease)?

 Physics Rules

Coulomb's Law of Electrical Interaction:
The electrical force exerted between two charged objects is directly proportional to the product of the quantity of charge on the objects (Q1 and Q2) and inversely proportional to the square of the separation distance (d) between the two objects. In equation form,
 
Felect= k • Q1• Q2/ d2

k is the constant of proportionality known as the Coulomb's law constant.

 Think About It

Equations are more than recipes for algebraic problem-solving. They are guides to thinking about how one quantity depends upon another. For instance, the Coulomb's law equation (see Know the Law section) provides a guide to thinking about which variables effect the electrical force and how the affect would be seen. The equation shows that the electrical force depends directly upon quantity of charge on both of the objects. So whatever change is made in the quantity of charge, the same change is made in the strength of the electrical force. And the equation shows that the electrical force depends inversely upon the distance of separation between the two charged objects. So whatever change is made in the separation distance, the opposite or inverse change is made in the strength of the electrical force.

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