A uniform magnetic field B exists in a region of size b × b. A square-shaped wire loop of dimensions a×a where a < b, mass m, and resistance R approaches this region. Vector B is perpendicular to the plane of the loop as shown. If the loop enters this magnetic region with the minimum speed allowing it to pass through, calculate the amount of time required for the entire loop to enter the region. Neglect gravitational effects.

(Submitted by José Ignacio Íñiguez de la Torre Bayo, Universidad de Salamanca, Salamanca, Spain)

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  • Haoqin Deng (Wuxi Big Bridge Academy, Wuxi, Jiangsu, China)

  • Norman Derby (Curry...

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