We have two bulb in parallel debiting 75 + 40 = 115 watts under 110 volts.
I -current amperes
V -potential volts
W -power watts
R -resistance ohms
knowing
W = V*I
V = I*R
W = R*I2
Then:
115 watts = 110 volts * I
=> I = 115/110 = 1,045 amperes
R = 115/(115/110)2 = 1102 / 115 = 105,217 ohms
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Another way:
First get the resistance of each bulb.
Then we know that Rparallel = 1/(1/R1 + 1/R2 )
75 watts = 110 volts * I => I = 75/110 ampere.
R1 = 75/(75/110)2 = 1102/ 75 = 161,333 ohms.
for the other bulb
40watts = 110 volts * I => I = 40/110 ampere.
R2 = 40/(40/110)2 = 1102/ 40 = 302,5 ohms.
meaning
Rparallel = 1/(1/161,333+1/302,5) = 105,217 ohms
That it's
Using Ohms law, the resistance can be calculated by using the following formulas. R = Watts/Amps (squared). R = Volts (squared)/Watts. R = Volts/Amps.
Just use Ohm's Law: V=IR (voltage = current x resistance; using units: volts = amperes x ohms).
A battery is rated to supply a certain number of volts. However, it actually supplies less, because they are "lost" as the current has to get out of the battery in the first place.(The battery has internal resistance)The amount of lost volts depends on the current being drawn:The less resistance a circuit has, the more current is drawn, because it's easier to flow.Example:If the circuit has little resistance, it draws a large current and the battery's internal resistance causes more lost volts.If the circuit has high resistance, it draws a small current and there are fewer lost volts.This is why when you short-circuit a battery (give it hardly any resistance to go through) it heats up and may explode. A large current is drawn and all the volts are used by the battery's internal resistance.
On this calculation I am assuming that the light bulb is using a 120 volt source. Watts = Amps x Volts. Amps = Watts/Volts, 40/120 = .33 amps. R = Volts/Amps, 120/.33 = 363.6 ohms resistance in the 40 watt light bulb.
3 amps
If they're connected in series the total resistance is 2000 ohms. If they're connected in parallel the resistance is 500 ohms.
4.5 volts in series; 1.5 volts in parallel.
36 volts
The voltmeter will register the volts, the ammeter will either explode or blow a fuse since it has a very low resistance and is designed to be used in series to measure the current flowing through it.
The total current in a circuit consisting of six operating 100 watt lamps connected in parallel to a 120 volt source is 5 amperes. Since power is volts times amps, take 600 watts (100 times 6) and divide by 120 volts to get 5 amps.
30 volts.
9 volts
the answer is 36 volts
8
That depends on the resistance connected. Use Ohm's Law: V=IR. Solving for current: I = V/R. If nothing is connected, there will be no current (infinite resistance).
Depends on how you connect them together. Connected them in a series and you will have 18 volts. Connected them in parallel and you will still have 9 volts just double the capacity of 1 battery. Click the link to see these 2 connections.
9 volts.