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The figure shows a cross section across a long cylindrical conductor of radius a = 1.78 cm carrying uniform current 49.8 A. What is the magnitude of the current's magnetic field at radial distance (a) 0, (b) 1.00 cm, (c) 1.78 cm (wire's surface), (d)2.20 cm? (a) Number Units (b) Number Units (c) Number Units (d) Number Units A solenoid 1.23 m long and 2.81 cm in diameter carries a current of 19.8 A. The magnetic field inside the solenoid is 26.2 mT. Find the length of the wire forming the solenoid. Number Units