I have a question about a battery charger setup. R in the diagram is a variable resistor. I'm trying to determine what the value of R is under 3 circumstances. 1st, a charging current flows at +4amps. 2nd, a power of 25w is delivered to the battery(.035ohm and 10.5v) I forgot to label the right side of the diagram battery to the right of the nodes. and lastly, what is the value of R with a voltage of 11v present at the battery terminals. Can this be explained better than the picture.
for 1) i used KVL
0 = 13 + 10.5  (0.02+0.035)  R*i1 ===> i1=4 and 0.02 and 0.035 can be combined cuz of series so I got
R = 0.68 ohms
for 2) I used R = (V^2)/P = (13^2)/25 = 6.76 ohm  0.02 ohm for the resistor on charger side == 6.74 ohm
3) us not solved yet, but assuming I can use the same situation? Unless I'm suppose to take overall voltage meaning 1310.5 for (2) and 1311 for (3) ? Can someone shed some light?
for 1) i used KVL
0 = 13 + 10.5  (0.02+0.035)  R*i1 ===> i1=4 and 0.02 and 0.035 can be combined cuz of series so I got
R = 0.68 ohms
for 2) I used R = (V^2)/P = (13^2)/25 = 6.76 ohm  0.02 ohm for the resistor on charger side == 6.74 ohm
3) us not solved yet, but assuming I can use the same situation? Unless I'm suppose to take overall voltage meaning 1310.5 for (2) and 1311 for (3) ? Can someone shed some light?
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