Power is measured in Watts,
power (Watts) = E (volts) x I (current - amps)
current is determined by the internal resistance (R) of the lightbulb, the lower the resistance the more current will flow.
120v x 0.5a = 60W
120V x 0.83a = 100W
the 100W lightbulb will draw more current
We also have Ohm's law: E(volts) = I (amps) x R (ohms)
Household voltage stays the same at 120v
we have for a 100w lamp:
120v = I x R
R = 120v/0.83 amps
R = 144.6 ohms
for a 60w lamp:
120v = I x R
R = 120v/0.5 amps
R = 240 ohms
The higher watt lamp has lower resistance.
xhunga kba? ?npakiana pluh kme
You don't. The output of a ballast is for one purpose only and that is to operate the lamp that is designed for that ballast. You should be careful with high output ballasts as they can draw enough milliamps to lock your muscles up if the current is shorted through you.
Divide the power rating (in watts) by the voltage (in volts). So if you use a 100 watt light bulb in a typical 110 volt lamp then it will draw 100/110 = .91 amps of current. Or plug a 1500 watt electric heater into a 110 volt wall socket and it will draw 1500/110 = 13.6 amps of current.
The filament is fine so that its electrical resistance can be quite high. It is also long, for the same reason. Usually it is coiled up to fit the length in the lamp. The heating effect of electric current is proportional to the current squared, time the resistance (I*I*R). Most of the effect is due to the current. The current through the filament must be limited to stop it melting. Adding resistance will do that. Taking resistance away increases heating. So, a low energy lamp has a very thin filament and a high energy lamp will have a thicker filament.
The purpose is twofold. First it is a transformer which steps up the voltage to an amount that will operate the lamp. Secondly it acts as a resistance for the lamp. Without it the flourescent lamp would keep increasing current flow until it would completely burn itself out.
xhunga kba? ?npakiana pluh kme
Assuming you are referring to house lamps, these are always connected in parallel with each other. Each lamp will draw a current, the value of which depends on the wattage of the lamps. As each lamp is added, the supply current will increase by the amount of current drawn by that lamp.
The current in a reading lamp would be a small part of the total current in a home. For example, a home may have 100 amp service, while a reading light may draw less than 1 amp, so about 1% of the total.
A lamp with a thick filament will draw more current. What restricts the current flow in the filament is the resistance of the filament which increases as the temperature of the filament increases. A thin filament requires less energy to get heated up that a thick one so less current to achieve threshold resistance. Also a thick filament provides a broader path for current so there is less resistance per increase in degree centigrade. For these two (closely related but distinct) reasons it will require more current for the filament to get heated up to threshold resistance.
No, a lamp plugged in but switched off does not draw electrical current. The switch on the lamp has the electrical circuit in the open position. In open circuits no current will flow. As soon as you close the circuit the lamp will start using power at a rate that is the wattage of the bulb. It is this wattage that you pay your utility company to supply.
It would be pretty much undefined, since the filament of the halogen bulb would fail immediately then there would be an open circuit with no current draw. <<>> The formula for current is Amps = Watts/Volts. The lamp itself would draw 4.16 amps. Since the voltage of the lamp is 12 volts there is a internal transformer involved in the fixture itself. It doesn't matter what the input (primary) voltage to the transformer is, so long as it meets the manufacturer's specification as to the proper voltage to operate the fixture.
You don't. The output of a ballast is for one purpose only and that is to operate the lamp that is designed for that ballast. You should be careful with high output ballasts as they can draw enough milliamps to lock your muscles up if the current is shorted through you.
A lamp with a thick filament will draw more current. What restricts the current flow in the filament is the resistance of the filament which increases as the temperature of the filament increases. A thin filament requires less energy to get heated up that a thick one so less current to achieve threshold resistance. Also a thick filament provides a broader path for current so there is less resistance per increase in degree centigrade. For these two (closely related but distinct) reasons it will require more current for the filament to get heated up to threshold resistance.
Can you show me how to draw an alcohol lamp?
There is no way to know for certain when the lamp will die, but when the light comes on, the power to the lamp has detected the increase in current, which is indicative of a lamp that is about to burn out. I would purchase a replacement lamp and have it on hand when the bulb goes out. I would expect you will get no more than a couple of weeks use from this old lamp.
The formula for current is Amps = Watts/Volts. The lamp itself would draw 4.16 amps. Since the voltage of the lamp is 12 volts there is a internal transformer involved in the fixture itself. It doesn't matter what the input (primary) voltage to the transformer is, so long as it meets the manufacturer's specification as to the proper voltage to operate the fixture.
Since power is volts time amps, the current in a 60W lamp connected to 120V is 0.5A. Since a lamp is a resistive load, there is no need to consider power factor and phase angle, so that simplifies the explanation. ======================== Assuming this is an incandescent or halogen lamp (using a filament to make the light) there is a trick here: the resistance of a lamp filament varies with temperature and does not follow Ohm's law. The resistance will be much lower, thus the current will be much higher when the filament is cold, when the lamp is first connected. As the filament heats up, the resistance increases until it gets to a steady operating point of 0.5A. For a halogen lamp, the operating temperature is about 2800-3400K, so the R at room temperature is about 16 times lower than when hot... so when connected, the current is about 8A but drops rapidly. The current could be even higher if the lamp is in a cold environment. Non-halogen lamps operate at a lower temperature and would have a lower initial current--about 5A. And this all assumes the lamp is rated for 120V. If it is a 12V/60W lamp, the filament will probably break and create an arc, which may draw a very large current.