# Battery and current

## Homework Statement

Please help!!! My problem is: (with figure attached, the figure explains the majority of the ptorblem)
(a) What is the size and direction of current i1 in Fig. 27-40, where each resistance is 2.2 and V1 = 18 V?

(b) What is the power of the 18 V battery, and is energy being supplied or absorbed by the battery?

(c) What is the power of the 10 V battery, and is energy being supplied or absorbed by the battery?

(d) What is the power of the 5.0 V battery, and is energy being supplied or absorbed by the battery?

V=iR

## The Attempt at a Solution

For part (a) I'm having trouble firguring out which resistances to use. Do I use all of the resistances and add them up according to whether they are parallel or perpendicular? Then, when I get the resistance that I need, do I just use the 10 V battery as my voltage to calculate the current? I tried adding all of the resistances and I got 8.64 ohms. Is this correct?

For part (b) I need to know again what resistance to use to calculate the current, which I would need to calculate power. If I can get some help on (b), I can probably do (c) and (d) by myself.

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