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**Homework Statement**

**1.**A battery is made up from a series combination of six 1.2 volt nickel cadmium cells supplying a 10ohm load-

**a)**What is the open circuit voltage?

**b)**Ignoring internal resistance, what is the current flowing in each cell?

**2.**The nickel cadmium cells in Q1 are reconnected in parallel and are connected to the same load-

**a)**What is open circuit voltage?

**b)**Ignoring internal resistance, what is the current flowing in each cell?

**3.**Determine the internal resistance of a carbon cell if the open circuit voltage is 1.70 volts and when a 10 ohm resistor is connected across the battery terminals the voltage falls to 1.26 volts.

**Relevant equations**

I=V/R

V=IR

**The attempt at a solution**

**1a**- Do i simply use V=IR which would be 6x1.2 = 7.2 V? Is that the correct answer?

**1b**- Using I=V/R, is it simply 7.2/10 = 0.72A (current doesn't change through a resistor in a series circuit right?)?

**2a**- Do the voltages of each cell coalesce within the parallel circuit or is the total voltage simply V=IR = 1.2V?

**2b**- Since I(current) isn't the same through each resistor in a parallel circuit, would it be 0.12A flowing through each cell?

**3**- I'm really not sure how to solve for this. Transposing the E(emf)= V - IR(internal) equation, I get R(internal) = (E - V)/I. But I'm not sure which value (ie 1.26 or 1.7V) goes where or how to solve this problem.

Any help is very much appreciated! Cheers