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Characteristics of non contact forces. (ICSE CLASS 9)

The properties of non contact forces( gravitational,  electrostatic and magnetic forces) are as follows,
1. They are central forces. It means the non contact force acts along the line joining the centres of two bodies.
2. They follow inverse square law. It means a non contact force is inversely proportional to the square of the distance.
3. They can both be attractive and repulsive.

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