# Pacemaker problem

1. Sep 13, 2006

### FlipStyle1308

Pacemakers which are designed for long-term use commonly employ a lithium-iodine battery capable of supplying 0.42 A x h of charge. (a) How many coloumbs of charge can such a battery supply? (b) If the average current produced by the pacemaker is 5.6 mcA, what is the expected lifetime of the device?

I am pretty sure I have to use the equation I = Q/t, so Q = It? How do I get t, since it is not mentioned at all? Does this have anything to do with the "x h" mentioned in the problem?

Last edited: Sep 13, 2006
2. Sep 13, 2006

### stunner5000pt

what unit make up an Ampere??

since I = Q/t
and time is in what units?

can you figure out how to d oyour problem now??

3. Sep 13, 2006

### FlipStyle1308

A = C/s, so C = As = (0.42)(3600) = 1512C. As for part (b), what is 5.6 mcA? I see the A, but was does mc mean?

Last edited: Sep 13, 2006
4. Sep 13, 2006

### stunner5000pt

mc = micro (althouhg usually they use the symbol mu $\mu$)

micro = 10^-6

5. Sep 13, 2006

### FlipStyle1308

Okay, I correctly solved this problem, thank you!