A car battery has a rating of 200 ampere·hours (A·h). This rating is one indication of the total charge that the battery can provide to a circuit before failing.

Question

What is the total charge (in coulombs) that this battery can provide?
Determine the maximum current that the battery can provide for 44 minutes.

Answer 1

An amp is a coulomb/second
So a coulomb = amp second

200 amp hours * 3600 s/hr = 720,000 amp seconds = 720,000 coulombs

44 minutes = 2640 seconds
i * time = charge = 720,000 c
i = 720,000/2640
i = 273 amps
(actually it would probably burn up, but that is another problem :)

Answer 2

amperes x seconds = coulombs.
200 x 1 hour = rating.
200 x 60 minutes = rating.
44/60 of that = ??