g coiled telephone cord forms a spiral with 71.0 turns, a diameter of 1.30 cm, and an unstretched length of 46.5 cm. Determine the inductance of one conductor in the unstretched cord.

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Answer(a)   the matererials that are in contact, the two materials and the nature of their surfaces/// (b)/// the force pushing the two surfaces together, pushing the surfaces together causes the more of the asperities to come together and increases the surface area in contact with each other