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There is a current of 0.83 A through a light bulb in a 120 V circuit What is the resistance of this light bulb?
Wiki User
∙ 14y ago
If a lightbulb has a resistance of 250 ohms, the voltage required for the bulb to draw a current of 0.5 A is 125 V. (Ohm's law: voltage equals current times resistance)
Unfortunately, its more complicated than that...
Is the resistance of 250 ohms the hot resistance or the cold resistance? It matters. It matters very much.
Light bulbs have a dramatic positive resistance to temperature coefficient. It is not uncommon for the instantaneous on power to be 10 or 20 times the nominal value.
So, if the 250 ohms is the measured resistance while operating at a current of 0.5 A, then 125 V is the correct answer. If the resistance is the cold resistance, you need to go back and find out the hot resistance at the desired operating point.
Wiki User
∙ 14y ago
Wiki User
∙ 16y agosimple ohms law calculation R= V/I, R= 210/.75 = 280 ohms
Wiki User
∙ 15y agoVoltage is equal to current over resistance. V=I/R which means that the resistance should be .0069167 ohms.
Wiki User
∙ 14y agoV=IR 120V = 0.83A * R R= (120V)/(0.83A) R= 144.57 Ohms
Wiki User
∙ 14y agoR = E / I = 120/0.5 = 240 ohms
Wiki User
∙ 14y agoV = I x R so R = V/I and 3/.4 = 7.5 Ohms
Wiki User
∙ 12y agoR = Volts / Amps
LETICIA COLLINS
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In a series circuit when adding light bulbs does the current change?
Yes. The current is inversely proportional to the resistance. I = V / R where I is current, V is voltage, and R is resistance. Adding light bulbs adds resistance. Current is constant throughout a series circuit; it doesn't change no matter what. Voltage changes.
What would happen to the current in a simple circuit if a bulb with a higher resistance were used?
Ohm's law applies: Current = Voltage / Resistance As such if you double the resistance of the light bulb you end up with half as much current.
How is an open circuit different from a short circuit?
I guess you could call them 'reciprocals' in a sense.-- "Open circuit". . . Has a very high resistance. Nominally infinite.. . . No voltage, no matter how high, is high enough to produce any current through the circuit.. . . Current through it is always zero.. . . Household example: a light switch that's open (labeled OFF in that position).-- "Short Circuit". . . Has a very low resistance. Nominally zero.. . . Any voltage, no matter how small, is enough to produce very high current through the circuit.. . . Household example: toddler stuck a paper-clip into the two holes of the outlet.
Compare the current in a 2 light bulbs wired in a series circuit?
Since the SAME electrons have to go through both light bulbs, the current in both light bulbs will be the same (Kirchhoff's current law).
How does the electrical resistance of an object change - If a light bulb has X ohms of resistance three of those light bulbs in the same circuit in series have less resistance?
The resistance of a light bulb is inversely proportional to its temperature, i.e. a cold bulb has less resistance than a hot bulb. As a result, if you connect three bulbs in series to the same voltage used for one, they will each receive one third of the original voltage, causing them to use less power, causing them to generate less heat, causing them to have less resistance. If you measure the current in the circuit, there will be slightly more than one third of the original current. Given the same voltage, that means that each bulb has less resistance than originally measured, as expected. This characteristic of light bulbs is why they tend to blow out at turn-on. The starting current and power is higher than in the steady state case. You can make a bulb last much longer if you provide a soft start circuit that ramps up the voltage over a short period of time.
What effect does decreased resistance have on a circuit?
resistance is the opposition to the flow of an electric current, therefore the current will decrease as the resistance increases. Resistance also creates heat. This is how the light globes in a circuit light up.
What is the current through each light bulb in a series circuit?
it remains same i=voltage/total resistance
What voltage is required to sustain a current of 0.50 through a light bulb resistance of 190?
The voltage of a circuit with a resistance of 250 ohms and a current of 0.95 amps is 237.5 volts. Ohms's law: Voltage = Current times Resistance
In a series circuit when adding light bulbs does the current change?
Yes. The current is inversely proportional to the resistance. I = V / R where I is current, V is voltage, and R is resistance. Adding light bulbs adds resistance. Current is constant throughout a series circuit; it doesn't change no matter what. Voltage changes.
How much resistance does a light bulb create if it has a current of 25 mA around it in a 9 V circuit?
how much resistance does a light bulb creat if iyt has a current of 25 mA around it in a 9 V circuit?
Why will the current flow be different in a heated rear screen circuit than a side light circuit?
the heated rear screen circuit has a higher resistance compared to the side light circuit
What would happen to the current in a simple circuit if a bulb with a higher resistance were used?
Ohm's law applies: Current = Voltage / Resistance As such if you double the resistance of the light bulb you end up with half as much current.
What happens to the current in a circuit if the resistance in increased.?
If resistance is increased, current decreases. Ohm's Law: current equals voltage divided by resistance.
What is the difference between a parallel circuit and a series circuit?
A parallel circuit is one in which there is more than one current path. An example might be several light bulbs in a house, all of which provide a path for electric current. The advantage is that any of the lamps can be turned on or off without affecting the current flow through any other lamp. A series circuit is one in which the current has only a single path through multiple components. An example might be two resistors, one after the other. Both will have the same current through them but they may have varying voltages depending on their resistance. Another example of a series circuit is a houehold lamp and a light switch. When the light switch is open, no current flows through it and therefore, no current can flow through the lamp either. When the switch is closed, current will now flow through the switch and the lamp.
How is an open circuit different from a short circuit?
I guess you could call them 'reciprocals' in a sense.-- "Open circuit". . . Has a very high resistance. Nominally infinite.. . . No voltage, no matter how high, is high enough to produce any current through the circuit.. . . Current through it is always zero.. . . Household example: a light switch that's open (labeled OFF in that position).-- "Short Circuit". . . Has a very low resistance. Nominally zero.. . . Any voltage, no matter how small, is enough to produce very high current through the circuit.. . . Household example: toddler stuck a paper-clip into the two holes of the outlet.
This circuit is a series circuit because?
the same current flows through both light bulbs
When the bulb is the resistance what this tells about the resistance?
An incandescent bulb has a filament that has a resistance. The value of the resistance determines the current that will flow for a given supply voltage. The heat generated by the current flowing through the filament gives off light. As the resistance of the filament decreases the current increases and you get more light.
