Parallel circuits question......Two resistors, 35.0 ohms 64.0 ohms, are connected in parallel.?

Question

Two resistors, 35.0 ohms and 64.0 ohms, are connected in parallel. The current through the 64.0 ohm resistor is 3.40 A.

(a) Determine the current in the other resistor.
(b) What is the total power consumed by the two resistors?

Any help is appreciated, I cannot figure out how to solve this without knowing the voltage across the power source????

Answer 1

In parallel, Voltage is equal in all Resistors, and Total Current is the sum of all the Currents in each Resistor.

(a). First find out the voltage:

V = IR

V = 3.40(64) = 217.6 volts

Now back to the 35 ohm resistor (same voltage):

V = IR

I = V/R = 217.6 / 35

Final answer:
I = 6.217 amps

(b) Wtotal = Itotal Vtotal

Add the Currents up and multiply by the Voltage

W = (6.217 + 3.40)(217.6)

Final answer:
W = 2,092.66 watts
.

Answer 2

Hi,
Well, there are different ways to do this, but let's do the following:
First let's say R1 = 35.0 ohms and R2 = 64.0 ohms.
1) Calculate the voltage across the 64.0 Ohm reistor. Remember that since this is a parallel curcuit, the voltages is the same across each resistor.
V= IR
=3.40(64.0)= 217.6 V
Part a:
2) Now, divide that voltage by the other resistance to find the current through the resistor:
I = 217.6/35.0
= 6.13
Part b:
3) P=VI
=217.5*(6.13+3.40)
= 2072.775
A little over 2 kilowatts. Just as a reality check, the average clothes iron is about 1200 Watts. Incidentally, the values of these resistors and the currect drawn are atypical high. Resistors in electronic devices are typically no more than 1 Watt.

Hope this helps.
FE

Answer 3

voltage is equal in a system that is in parallel. Therefore, the voltage across the 64 ohm resistor is:

V=IR -> V = 3.4A * 64ohm = 210ish (you can do exact calculation)

Now, this voltage is the same for the 35 ohm resistor. Therefore the current for it is:

I = 210ishV/35ohm

Total power consumption is P = I^2 * R.

The easiest would be since you know the voltage combine the two resistors to a equivalent resistance. Then all you have to do is use the voltage and resistance to calculate the total current draw (or just sum the two currents together you calculated earlier).

Answer 4

Together , the two resistors present an equivalent resistance of 35*64/(35+64) = 22.626 ohms.

Voltage across the 64 ohm resistor 64* 3.4 = 217.6 volts.
This same voltage is across the 35 ohm resistor so the current through the 35 ohm resistor is 217.6/35 =6.22 amps.
The current entering the paralle resistirs is 217.6+22.626 =
9.62 amps which is = 3.4+ 6.22 A

Now you can comput power = I^2R or E^2/R

Answer 5

Hello NC Gal...
Answer from NC Fellow in Arapahoe

I = E / R 3.40 Amps = E / 64

E = 64 x 3.40 = 217.6 Volts

Other Resistor Current Flow...

I = E / R I = 217.6 / 35

I = 6.217 Amps

B.) Power (in watts) = I X E

first resistor P = 217.6 Volts x 3.4 Amps = 739.8 Watts
Second resistor = 217.6 Volts x 6.217 Amps = 1352.8 Watts

Total power through both resistors =

739.8 + 1352.8 = 2092.6 Watts

regards,
w4hsa @ pamlico.net

Answer 6

the total resistance will be 5 m Ohm, since when resistances are connected in parallel, calculate the net reisitance as: (1/1000)*5 = (5/1000) = 5m Ohm.

Answer 7

Don't cheat.

Do your own homework.