Electrical= Resistance and Energy

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A wire with a resistance of 9.0 ohms is connected to a 3.0 V battery with an internal resistance of 1.0 ohm. The energy transferred from chemical to electrical form in 4.0 minutes is calculated to be 216 joules. The initial calculation for thermal energy in the wire was incorrect at 189.629 joules, prompting a discussion about the impact of the battery's internal resistance on the overall circuit. The correct thermal energy calculation, considering the internal resistance, led to a revised answer of 194.4 joules. The importance of accounting for the battery's resistance in energy calculations was emphasized in the discussion.
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A wire of resistance 9.0 is connected to a battery whose emf is 3.0 V and whose internal resistance is 1.0 .
(a) How much energy is transferred from chemical to electrical form in 4.0 min?
(b) How much energy appears in the wire as thermal energy in that time?

answer to a= 216 (that's correct)
for b, i got 189.629 (that one is wrong though)

For the work, i did: I= 3V/9 = .3333 A
Vtotal= 3V-IR
Vtotal= 3V-.333(1)
Vtotal= 2.6666
p=Vsquared/R
P=2.666 squared/9
P= .79011
.79011 (4) (60) = 189.62
 
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When calculating the current -- why would you ignore the resistance of the battery? (Normally you would, but in this case it is a fairly high component of the overall resistance of the circuit)
 
i would ignore it because its asking for the energy in the wire specifically..i believe anyway
 
if for a new answer, i got 194.4 joules..would that be correct?
 
is 194.4 the answer?
 

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