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Metals that make up typical resistors (and many other electrical components for that matter) tend to heat up as current flows through them. "COLD" resistance is the resistance before it is operating and "HOT" resistance is the resistance after some operating time has elapsed.
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What is the resistance of a fuse bulb?
A lamp has two resistances: a 'hot' resistance (its operating resistance) and its 'cold' resistance (its resistance when switched off), and the hot resistance is significantly higher than its cold resistance.You can calculate its 'hot' resistance from its rated power and its rated voltage (assuming that it is being supplied at its rated voltage), by manipulating the following equation, to make Rthe subject: P= V2/RYou will, though, have to measure its cold resistance.
What is meant by cold resistance of filament lamp?
It means exactly what it sounds like. The resistance of an incandescent bulb's filament depends on its temperature. A filament has a positive temperature coefficient, which means that its resistance increases as its temperature increases. A typical 40 watt bulb (120 volts) has a cold resistance of about 28 ohms, but its hot, operating resistance is about 360 ohms. If the cold resistance were constant, the bulb would dissipate 379 watts. In fact, cold turn on is the most stressful time for a bulb.
What is the resistance of a lightbulb using Ohm's law?
By Ohm's law, resistance is voltage divided by current, so the resistance of a light bulb can be measured by observing the voltage across it simultaneously with observing the current through it. Interestingly, the hot resistance is significantly different that the cold resistance, so measuring resistance with an ohmmeter will not give a meaningful resistance. This is because the resistance of a light bulb has a positive temperature coefficient. Take a typical 60 W 120V light bulb, for instance... Its cold resistance is about 16 Ohms. Calculate current and power at 120 V and you get 7.5 A and 900 W. The truth is that at 60 W, the bulb pulls 0.5 A and has a resistance of 240 Ohms.
Does the resistance go higher or lower when a thermistor gets hot?
the therminster will get hotter when the resistance is lowed
What is isolation resistance?
I think you mean, 'insulation' resistance! It's the resistance of insulation, normally expressed in megohms.
What are cold resistance and hot resistance?
Metals heat up as electrical currents flow through them. Cold resistance is the metals resistance before it is operating. Hot resistance is the metals resistance after operating time has elapsed some.
How does temperature affect resistance of a wire?
If you are asking if a hot wire has a greater resistance than a cold wire then the answer I would say is yes. Cold wires have always had less resistance than hot wires
What Does blizzard mean hot or cold?
It mean cold.
What is the resistance of a fuse bulb?
A lamp has two resistances: a 'hot' resistance (its operating resistance) and its 'cold' resistance (its resistance when switched off), and the hot resistance is significantly higher than its cold resistance.You can calculate its 'hot' resistance from its rated power and its rated voltage (assuming that it is being supplied at its rated voltage), by manipulating the following equation, to make Rthe subject: P= V2/RYou will, though, have to measure its cold resistance.
Does decrease mean cold or hot?
temperature decrease is cold temperature increase is hot
What does it mean if a guy is hot and cold with you?
I am a teen myself, and i say being hot and cold is an on(hot) and off(cold) relationship.
How sings hot in cold?
u mean hot AND cold? Katy perry
Cold and heat fatigue resistance?
Cold and heat fatigue is one of the main forms of failure of hot work dies, and the molds for supporting pictures should have high resistance to cold and heat fatigue.
Can hot air or cold air effect how far a person hits a golf ball?
Yes, in hot air the air is a lot thinner so there is less resistance compared to cold air which is a lot denser so more resistance.
What word mean very hot and very cold?
FIRE for HOT andICE for COLD
What is mean by hot working and cold working?
When ur hot and ur working then it is hot working, if ur cold and ur working then it is cold working
1996 vw sharan heater blows cold cabin hot?
can you please clarify what you mean, do you mean that the front heater blows cold but the rear blows hot or do you mean that when the heating is on cold it blows hot? many thanks paul
