Please answer all parts SHOWING ALL STEPS CLEARLY EXPLAINING THE CONCEPTS and make sure all are 100% correct solutions. Do NOT use calculus (Integration, Cross product, etc.) to solve any of them. Thank you very much!

Consider the toroid shown in the figure (inner radius 5 cm, outer radius 10 cm). What is the magnitude of the magnetic field inside a toroid of 1200 turns carrying a current 0.8 A at a distance 7 cm from the center of the toroid? (Hint: Use Ampere's Law applied to a closed loop in the toroid mid-plane, as + shown by a dashed line.) (1) 2.74 mT (2) 1.67 mT (3) 3.33 mT (4) 4.92 mT (5) 0.83 mTConsider the circuit shown in the figure with L = 360 mH. After the switch 30 has been closed for a long time, what is the current in the inductor? 3120 + 120 90 V LA large MRI magnet is a large solenoid (with superconducting wires having zero resistance) with diameter 0.60 m and length 1.8 m. During normal operation, the current through the windings is 110 A and the magnetic field magnitude is 1.3 T. What is the energy stored in the MRI magnet? (1) 0.34 MJ (2) 0.44 MJ (3) 0.68 MJ (4) 0.54 MJ (5) 1.37 MJ Refer to the previous problem. How many total windings does the MRI magnet have? (1) 16,900 (2) 9,400 (3) 13,000 (4) 15,500 (5) 14,700 A special kind of circuit breaker trips when the peak current exceeds 30 A. How many 150-W lightbulbs can be plugged into a standard 110 V (&rms = 110 V) outlet without tripping the breaker? (1) 15 (2) 20 (3 28 (4) 31 (5 22