PHY 114 Lecture Notes - Lecture 2: Electric Field, Net Force, Hydrogen Atom
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The magnitude of the force between two point charges is: Where q1 and q2 are the charges, r is the separation between the two charges. K = 8. 99 x 109 (cid:3015) (cid:3040)(cid:3118)(cid:3004)(cid:3118) . And (cid:2869) (cid:2872) (cid:2976) (cid:2965)(cid:3116) 0 = 8. 85 x 10-12 (cid:3004)(cid:3118)(cid:3015) (cid:3040)(cid:3118) And 0 is called the permittivity of free space. The electric force is directed between the centers of the two point charges. Shows arrows of the two forces pointing from the centers of the objects towards each other. The radius is from the center of the two objects. Shows arrow of the tow force pointing from the centers of the objects away from each other. The radius is still from the center of the two objects. The electric force is an example of a long-range or field force, just like the force of gravity. Compute the force between two people at "arms length" from each other if they each have a 1% excess of electrons.