2007-03-18 06:50:13 · 12 answers · asked by mina t 1 in Science & Mathematics ➔ Engineering
you can change the brightness by changing the power that is going round the circuit. change the voltage loweer and it gets dimmer make the voltage lower and iottl get dimmer.
also if the circuit is in series, you can make it dimmer by adding more bulbs and brighter by taking off some number of bulbs.
2007-03-18 06:54:18 · answer #1 · answered by Anonymous · 0⤊ 0⤋
ATTENTION: A light dimmer in a house is NOT a rheostat. It is something called a triac. It is specific for high-voltage Alternating Current (the electricity in your house.) If you are running off a battery (Direct Current), you want to use a rheostat.
A rheostat, also called a potentiometer, can be bought at RadioShack or an electronics store. The packaging will show how to connect it. If you connect it before or after the lightbulb in a circuit, turning the knob will lower or raise the voltage, thus changing the bulb's brightness.
A light dimmer will NOT work.
2007-03-18 23:31:54 · answer #2 · answered by ◄DiscoAsimov► 2 · 0⤊ 0⤋
well some one has to get up to date and call the device a potentiometer which is a variable resistor and are commonally available from places like maplins and rs components. they cost a few pence but too much resistance will stop your bulbs entirely.
the amount of power (currant )which flows through the system is controlled by the potetiometer and this varies the light output of the lamp.
if you`ve got worries about this setup then do asearch on yahoo or google and put in basic electronics it will come upwith something. added the first one on that search in the reference section.
the bit for extra credit at schoolis to mention ohms law which is the relationship between power voltage and resistance or i=v/r i think thats v over r .i means amps v means voltage and r equals resistance so if you divide the amps by the resistor then you will get the amount of power that you are using.
be careful though if you are using much more then about 24 volts the potentiometer will start to get hot after extended periods so you could burn you`re self after many hoursof experimenting
2007-03-19 06:19:00 · answer #3 · answered by strange_bike 2 · 0⤊ 0⤋
if you have a basic circuit just put in a variable resistor, you can regulate the resistance therefore regulating the current which will then make your bulb brighter or dimmer
2007-03-20 15:41:24 · answer #4 · answered by liamgrayhurst 1 · 0⤊ 0⤋
if the circuit is in series, you can make it dimmer by adding more bulbs and brighter by taking off some number of bulbs.
2007-03-18 13:54:40 · answer #5 · answered by tyroneskee 2 · 0⤊ 1⤋
It's called a rheostat, more commonly called a dimmer switch used in many houses now. They vary the power through resistance of a coil of wire being rubbed by a contact. The contact is moved up or down the coil to change the voltage. Less coils=more volts, more coils= less voltage. The less wire the volts have to travel through allows more volts to flow.
2007-03-18 17:53:04 · answer #6 · answered by Anonymous · 1⤊ 0⤋
By varying the current by using a variable resistance in the circuit. The dimmer switches used in many houses is an example.of just this.
2007-03-18 13:56:06 · answer #7 · answered by Anonymous · 1⤊ 0⤋
Fit a dimmer switch in the circuit. They are available from most hardware shops or electrical retailers. Consult an electrician if you are not sure how to fit it.
2007-03-18 14:01:48 · answer #8 · answered by Bill D 3 · 1⤊ 0⤋
You can vary the voltage. Too much and you will blow the light bulb. If you put a reostat in the circuit, you can vary it on a dial.
2007-03-18 13:53:53 · answer #9 · answered by science teacher 7 · 1⤊ 0⤋
There are lots of ways but the simplest is to put a resistor in series with the bulb
2007-03-21 15:33:16 · answer #10 · answered by Professor 7 · 0⤊ 0⤋