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# physics help watch

1. Ok so basically, a circuit has an EMf of 12V, and the internal resistance is 2.0 ohms. There are 2 resistors, with a resistance of 30 ohms (the q doesnt say whether each)

The question is what the total current in the circuit is.

My method to work this out was

I = EMF/R +r, where R is the Internal resistance and r is the resistance in the resistors. This gave me 0.375A. Is that correct?
2. please i need help. How would i work this current out from the total circuit
3. (Original post by brownguytorule)
Ok so basically, a circuit has an EMf of 12V, and the internal resistance is 2.0 ohms. There are 2 resistors, with a resistance of 30 ohms (the q doesnt say whether each)

The question is what the total current in the circuit is.

My method to work this out was

I = EMF/R r, where R is the Internal resistance and r is the resistance in the resistors. This gave me 0.375A. Is that correct?
Are the resistors in series?

If so i would just use emf=IR, rearrange for current then sub in the emf and total resistance of circuit including the internal resistance

If the total resistance of the two resistors is 30 ohms then ur answer is right. If each resistor is 30 ohms ur off.
4. (Original post by Shaanv)
Are the resistors in series?

If so i would just use emf=IR, rearrange for current then sub in the emf and total resistance of circuit including the internal resistance
yes the resistors are in series
5. (Original post by brownguytorule)
yes the resistors are in series
I edited my above post. Ur answer is right if the external resistors have a total resistance of 30 ohms
6. (Original post by Shaanv)
I edited my above post. Ur answer is right if the external resistors have a total resistance of 30 ohms
ok. Thanks for the help
7. (Original post by brownguytorule)
Ok so basically, a circuit has an EMf of 12V, and the internal resistance is 2.0 ohms. There are 2 resistors, with a resistance of 30 ohms (the q doesnt say whether each)

The question is what the total current in the circuit is.

My method to work this out was

I = EMF/R +r, where R is the Internal resistance and r is the resistance in the resistors. This gave me 0.375A. Is that correct?
The format of the way u laid ur working out looked weird at first. However i just realised u have done exactly what i said. Maybe put brackets around the (R+r) next time for clarity
8. (Original post by Shaanv)
The format of the way u laid ur working out looked weird at first. However i just realised u have done exactly what i said. Maybe put brackets around the (R+r) next time for clarity
oh yeah. Sorry.

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