Newton's law of universal gravitation is designed to satisfy Kepler's third law.

The other two laws are related to the concepts of angular momentum and central force.

The angular momentum (L) of a particle about an origin O is the vector product of the position vector r and the linear momentum m·v.

The variation of L depends on the torque acting on the particle. If the force causing the torque is a central force, then the angular momentum of the particle about the centre is equal to zero and the angular momentum remains constant.

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