Okay, I thought I understood this but my homework site is telling me otherwise. What I did was add the total votage and came out with 40.12. I'm not sure if that is what I'm suppose to do or not for part (a).
Three resistors are connected in series across a battery. The value of each resistance and its maximum power rating are as follows: 5.0 and 20.5 W, 31.5 and 10.0 W, and 15.0 and 10.0 W.
(a) What is the greatest voltage that the battery can have without one of the resistors burning up?
V
(b) How much power does the battery deliver to the circuit in (a)?
W
If I know (a) then I should be able to do (b) by myself
2007-02-02 08:40:12 · 4 answers · asked by Confused 1 in Science & Mathematics ➔ Physics
Wow, thanks for the help everyone. I understand now. I was summing up the totals of all the resistors instead of looking at each one individually. Thanks.
2007-02-02 09:06:50 · update #1
I think that you can do "a" also if you had a hint. I would be happy to do a completely but after the hint stop reading and try it.
In a series circuit it is the current that is the same in all resistors.
What is the max current that each resistor can handle?
OK here is the rest
P = I^2 R
so I = sqrt(P/R)
2.025 Amp
.563 Amp
.816 Amp
So the max current is 563mA where the middle resistor is at its max.
Now the total resistance is 51.5 ohm so the voltage with that current is 29 volts.
2007-02-02 08:54:52 · answer #1 · answered by Roy E 4 · 0⤊ 0⤋
In series dc current, the current (I) is constant and the voltage drops across each resistance.
Ohms law says V=I*R
Power says W=V*I
Thus, W=(I^2)*R
So, substitue the max wattage at each resistor and look for the weakest link. Solve for the smallest value of I.
Substitute that value of I into ohm's law for the total resistance in the circuit and solve for V total.
Then solve for W=I * V total.
That should do it.
2007-02-02 08:55:50 · answer #2 · answered by Jerry P 6 · 0⤊ 0⤋
Twinkle twinkle little star, power = Isquared R.
find 20.5/5, 10/31.5 and 10/15
10/31.5 = 317 mA max current before possible burn out.
total R = 51.5 ohms V=IR = 16.3 (..255) Volts will be 0.317 amps
2007-02-02 08:51:03 · answer #3 · answered by bubsir 4 · 0⤊ 0⤋
i dont have a diagram yet parallel each and every of how guy you ought to blow you audio gadget in case you do sequence. on the amp there could be marking hook up the speaker wires to the wonderful polarities and make small adjustment right here and there.
2016-11-24 19:43:59 · answer #4 · answered by corral 4 · 0⤊ 0⤋