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6
The Field Concept
6.1 WHAT IS THE CONNECTION?
Consider the following situations: a charged rod attracting or repelling a charged
balloon, a magnet attracting or repelling a compass needle, a ball either thrown or
released falling to the ground, the moon kept in an orbit around the earth, and the
earth in orbit around the sun. What do all of these things have in common? Again,
think about this.
For one, all these situations involve forces, either attractive or repulsive. But in
addition, there is something special about these forces. Do you see it? In all of these
cases there is no contact between the interacting objects. Have you ever wondered ...