PHYS208 Fundamentals of Physics II

Answer for Ch. 28, 48P

I labeled the currents as i.1 (through emf.1 and R.3), i.2 (through emf.2 and R.2), and i.3 (through R.1). Why did HRW not switch the labels of R.1 and R.3 -- it would have made a lot more sense!

i.1:  421 mA to right
i.2:  158 mA to right
i.3:  263 mA down
of R.1:  346 mW
of R.2:  50 mW
of R.3:  709 mW
total dissipated:  1.10 W
total provided by emf.1:  1.26 W
total absorbed by emf.2:  0.16 W

Note that since the current through emf.2 is going in the opposite direction to its polarity, it is being re-charged (receiving power from emf.1).

Last updated Sept. 16, 1997.
Copyright George Watson, Univ. of Delaware, 1997.