Someone please explain how to do this MCQ.

Question

anonymous · Answer

attachment

mrnood · Answer

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First of all consider the 2 resistors in Parallel (6 and 3)

Work out the equivalent resistance of just those 2

THEN you have the 2 ohm + the 'equivalent resistance' in series, so you can work out the total resistance.

Then you have V , you have total resistance

I - V/R so you can calculate the current

anonymous · Answer

@MrNood : The answer is 1.0A. I'm not getting it by this method. O.o

anonymous · Answer

This is a question from Cambridge International Examination. Their official marking scheme says 1.0A. >_<

mrnood · Answer

OK - I'm sorry - I didn't read the question properly

mrnood · Answer

My answer was for the total current - I didn't see that I refers to current through the 6ohm resistor only

mrnood · Answer

Using my answer you can see that the parallel resistors are equivalent to 2ohms

since the other resistor is also 2 ohms the voltage between the 2ohm and th eparallel must be 6V

Therefore you have 6V across a 6 ohm resistor  -> 1 amp

anonymous · Answer

Oh, got it now. Thank youuu so much. ^_^