A flat search coil containing 1200 turns of wire is used to monitor the decay of a magnetic field inside a laboratory apparatus. The average cross-sectional area of the search coil is 3.0 × 10-4 m2. During a calibration run, the magnetic flux passing perpendicularly through the plane of the coil decreases uniformly from 1.8×10−4 Wb1.8 \times 10^{-4} \text{ Wb}1.8×10−4 Wb to zero in a time interval ttt. This decay induces an average electromotive force (e.m.f.) of 3.6 V across the terminals of the coil.
What is the value of ttt?
5.0×10−5 s5.0 \times 10^{-5} \text{ s}5.0×10−5 s
1.8×10−5 s1.8 \times 10^{-5} \text{ s}1.8×10−5 s
0.060 s0.060 \text{ s}0.060 s
17 s17 \text{ s}17 s
