Signed transport is not total passage

A 20-turn coil has resistance 2 Ω and negligible inductance. Flux per turn varies linearly between the table’s points. Positive current follows the right-hand direction associated with positive flux.

Constructed piecewise-linear flux history per turn.
t / s	Φ / mWb
0	0
0.20	6
0.40	2
0.60	−2

What is the signed net charge transported through a wire cross-section from 0 to 0.60 s?

Organize the givens & assumptions

20 identical turns
Resistance: 2 Ω
Table gives flux per turn, not total linkage

Closed circuit; constant resistance; inductive transients neglected; signed transported charge means the integral of current, not charge accumulated on the coil.

A $+0.020\ \mathrm C$
B $-0.020\ \mathrm C$
C $+0.0010\ \mathrm C$
D $0.140\ \mathrm C$

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