Count both field boundaries

A rectangular loop has transverse height 0.20 m, length 0.40 m along its motion, and resistance 2 Ω. It is pulled rightward at constant 2 m/s from completely outside, through, and completely out of a 1.20 m wide strip of 0.50 T field directed into the page.

What total heat is generated by complete entry and exit?

Organize the givens & assumptions

Loop height: 0.20 m; length: 0.40 m
Speed: 2 m/s
B=0.50 T into page
R=2 Ω; field-strip width 1.20 m

Rigid closed loop; negligible self-inductance, fringe fields and resistance change; an external agent maintains constant speed.

A $0.004\ \mathrm J$
B $0.008\ \mathrm J$
C $0.016\ \mathrm J$
D $0$

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