An electric lamp of 100ohm,a toaster of 50ohm & heater of 500ohm are connected in parallel to 220Vsource.?

Question

What is the resistance of electric iron connected to the same source that takes as much current as all three appliances and what is the current through it?

Answer 1

fisrt find the resistance equivalent of these 3 loads,

1/Req = 1/R1 + 1/R2 + 1/R3
1/Req =1/100 + 1/50 + 1/500
1/Req = 0.01 + 0.02 + 0.002
1/Req = 0.032
Req = 1/0.032
Req = 31.25 ohm

This is the resistance of the electric iron, 31.25 ohm.
Since the source voltage is 220 V, then the current thru it is

I = V/R
I = 220 / 31.25
I = 7.04 Amps , current passing to this electric iron.

Answer 2

1/100 + 1/50 + 1/500 = 1/31.25

The amperage of the circuit will be 7.04 amps. (220 v divided by 31.25 ohms).

Hook an electric iron with 31.25 ohms resistance in parallel with those other three devices, and the original three will get half the amperage, while it'll get half the amperage.

The current through it will be 3.25 amps.

Answer 3

This uses Ohm's Law: V =R*I. Since the appliances are in parallel, the voltage is the same through all of them. So calculate the current through each. It's V/R. Then add them together. Then to find the resistance of the iron, take V/I

Answer 4

Using the parallel resistance equation to find the effective resistance of the 3 parallel resistors

1/R = 1/R1 + 1/R2 +1/R3

1/R = 1/100 + 1/50 + 1/500

R = 16/500^-1
so R = 31.3ohms


So the total current in the circuit = 220V/ 31,3ohms

= 7.0A

I'm assuming he iron is in series with the resistors so its current = 7.0A and its resistance would be 220V/7A

= 31.4ohms

Answer 5

1/Rtot = 1/R1 +1/R2 = 1/R3

so 1/Rtot = 1/100 +1/50 + 1/500 = 16/500

so Rtot = 500/16 = 31.25 (also the equivalent resistance of the iron)

now use Ohms law V=IR

I tot = V/R = 220/31.25 ; Itot = 7.04 amps (also the current through the iron)

Answer 6

Hint:

Google "Ohm's law".
-