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That is e.g. the resistance of a cold bulb before the bulb is lighted and heats up.
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∙ 15y ago
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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 is one advantage of using genetic modification?
Some advantages are that they can make plants pest resistance, disease resistance, cold resistance, bigger in size and tastier.
How much current is needed to light a bulb with 180 ohms of resistance using 120 volt power source?
V = I x R so current I = 1/2 amp. I bet the bulb is rated at 60 W because Watts = Current x Voltage. Where V = voltage (volt) I = current (ampere) R = resistance (ohm) Your question isn't easy to answer. A lamp has two 'resistances': a 'cold' resistance, and a 'hot' resistance. Before it is energised, it is cold, so its resistance is low; when it is energised, it becomes very hot, and its resistance increases significantly. So, the question is whether your '240 ohms' is the cold resistance or the hot resistance. If it is the cold resistance, then a current of 0.5 A will flow through it for a fraction of a second, then its resistance will increase significantly, and the current will fall to a very much smaller value.
Does the resistance of a light bulb filament change after the light has been turned on?
The electrical resistance of a light bulb increases when it is turned on As a resistor, the tungsten light bulb has a positive resistance coefficient. This means that the electrical resistance goes up when the filament becomes hot. For example, a 100 watt light bulb operated at 120 volts - it does not matter if it is AC or DC for this calculation - will have a resistance of 144 ohms when hot and draw .833 ampere. When cold the filament typically has a resistance of only 10 ohms which increases as the filament heats up.
Why powerful lamps have lower resistance than less powerful lamps?
Power is voltage squared, divided by resistance (P = V2/R) so, for a given voltage, the lower the resistance, the greater the power!
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.
Why does being cold lower your resistance to cold virus?
Being cold doesn't lower your resistance. Viruses are acquired from other humans regardless of your temperature.
What do you mean by 'cold resistance' and 'hot resistance'?
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.
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.
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
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.
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 one advantage of using genetic modification?
Some advantages are that they can make plants pest resistance, disease resistance, cold resistance, bigger in size and tastier.
What word describes the Phenomenon when resistance of electricity stops at cold temperatures?
Superconductivity.
At very cold temperatures what loses all resistance to the flow of electricity?
Superconductorssuperconductors
Who is using pedimune medicine?
Used for children for gaining resistance from cold, cough and weakness
When is it safe in the spring to swim in your pool?
This is your choice and depends especially to your resistance to cold water.
