18. A single circular wire loop of radius 0.2 m and resistance 2 Ω is placed in a time-dependent magnetic field B as given in Fig.10. The plane of the loop is perpendicular to B. What is the current induced in the loop? (A) 0.019 A at t=0.5 s (B) 1.5 A at t=1.0 s (C) It reaches a maximum within t=2.0 to 4.0 s. (D) 0.03 A within t=4.0 to 6.0 s (E) None

19. A parallel plate capacitor (without a dielectric) is connected in series to a resistor and an AC voltage source. Considering a point between the two plates of the capacitor, which statement is correct? (A) No magnetic field exists because there are no moving charges. (B) Electromagnetic waves are constantly propagating outward between the plates. (C) The direction of the magnetic field is reverse during charging and discharging of the capacitor. (D) The direction of the magnetic field is the same during charging and discharging of the capacitor. (E) Both ( B ) and ( D ) are correct.

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