PhysicsPlease help
posted by Sally on .
I need a little direction with this question:If someone could provide the correct formula, I think I divide each reistor by 12V but I'm not sure. To find total resistance, do I just add the reciprocals?
Three resistors connected in parallel have individual values of 4.0, 6.0 and 10.0 W, respectively. If this combination is connected in series with a 12.0 V battery and a 2.0 W resistor, what is the current in each of the resistors and what is the total resistance of the circuit?
a. 0.59 A
b. 1.0 A
c. 11.2 A
d. 16.0 A

Please irnore the multiple choice answersthey were for a different problem that I copied down

find total resistance of the parallel network. I assume you mean ohms, not watts on the reistors.
1/Rt=1/4+1/6+1/10=1/60 (15+10+6)=31/60
Rt=60/31
Now add that inseries to 2 ohm, or total resistance is 151/60
current= V/R=12(60/151) check that
now, having total current, how does it divide in the paralel branch.
the voltage across the parallel branch is Rt*It= 60/131*69/151)
so current in each resistor is that voltage divided by either 4,6, or 10 ohms 
Thank you for your helpI can really use the explanation for my other problems too.
Thank you again 
I have another questionI looked closely at the explanation and when you added the three resistors together you came up with Rt=60/31. Then you added the series to the 2Ohm and said total equals 151/60I'm lost there because 2 Ohms would equal 30/60 or when added to the inseries it would become resistance total = 60/61 so where does the 151/60 come from? Sorry if I'm just not understanding

I figured it outthank you