A very long straight wire carries current 15 A. In the middle of the wire a right-angle bend is made. The bend forms an arc of a circle of radius 27 cm, as show. Determine the magnetic field at the center of the arc.

Ithink the answer is a

Answershe should not have multiplied the sulfur atoms by the subscript 4

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

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