Work done of charger of a battery

AI Thread Summary
The discussion revolves around calculating the work done by two batteries in a circuit where a 4V battery charges a 2V battery with a current of 2 Amperes. The initial calculation for the whole circuit's work done is determined to be 4 Joules, but there is confusion regarding how to calculate the work done by each battery individually. Participants clarify that work is calculated using voltage multiplied by charge, and there is a mix-up between work and power. The conversation highlights the importance of understanding the correct dimensions in physics equations. Ultimately, the thread reflects a light-hearted acknowledgment of mistakes made due to sleepiness.
FaroukYasser
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NEVER MIND! I realized my question is kind of stupid. Its night here and I am kind of sleepy. :))

Homework Statement


a battery of 4V is connected opposite to a battery of 2V to charge the 2V battery. assume the current running through the circuit to be 2 Ampere. What is the Work done by
1) the Whole circuit
2) By the 4V battery
3) by the 2V battery

Homework Equations


Work = Voltage x Charge

The Attempt at a Solution


1) I know that 2 A is 2 Columb/second. and since the two batteries are opposite the whole circuit work done is (4 - 2)V x 2 Columb = 4 J
2) for part 2 and 3 I am not sure I I should consider each battery by its own or what to do?
Also if we do do consider both, Isn't the current flowing in the 2V in the opposite direction of its positive terminal therefore makes it negative Work done! (work done is scalar)
a little clarification and a little help with the question would be really appreciated :))
Thanks
 
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Voltage x Charge doesn't give you the correct dimension. Voltage x Charge/time does. Charge/time is also known as current.
[edit] Oops :redface:, my mistake. Tooooo quick. Work is what you want, not power.
[edit2] Is this really the full text of the exercise ?
[edit3] Night here too; only now do I read the very first line... Oh well, :smile:
 
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BvU said:
Voltage x Charge doesn't give you the correct dimension. Voltage x Charge/time does. Charge/time is also known as current.
[edit] Oops :redface:, my mistake. Tooooo quick. Work is what you want, not power.
[edit2] Is this really the full text of the exercise ?
[edit3] Night here too; only now do I read the very first line... Oh well, :smile:

Hahahahaha No problem man :D :D Sleepiness does more :)) :D
 
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