0
Light energy W= qV=hf , then light frequency or color depends on energy qV here V is volts.
Thus, f = qV/h = (240Thz/volt) V indicating infrared frequency/volt.
Wiki User
∙ 10y ago
Add your answer:
Earn +20 pts
Why does LED light not separate after passing through a prism?
If the light is a pure color, just one frequency, then there is nothing to separate.
How many watts can an led need to light up?
It depends on the color of the led you have. Normally it changes between 1.5 V and 2.5 V. But if you need to use white or purple leds those leds need more power like 4-5Volts. Im gonna calculate for a standart red led, a red led needs 20 mA and 2 volts to light up. So we know the formula that we can calculate how many watts does the led need, P = U * I P = 2 * 0.02 = 0.04 W. I used the average values. I hope I didnt make any mistake :)
How does a rope light work?
There are many varieties of rope light. The biggest difference would be either LED or incandescent bulbs. Standard rope lights have two wires which can be controlled with a dimming or flashing controller. For chasing ability (lights run down the rope) at least three wires are required which can be controlled with a chasing controller. Rope lights are made of a PVC tubing which surrounds bulbs that are typically spaced 1" apart. LED rope light will have diodes while incandescent rope light contains small incandescent bulbs. Another difference between LED and Incandescent rope light is that the incandescent PVC tube contains color while the LED PVC tubing is clear and the color is given off by the diodes themselves.
Will a infrared led kept in sunlight glow or not?
There is no such thing as and an infra-red LED. Nor will an any LED glow without a power source. That power may come from a solar cell but an LED (Light Emitting Diode) emits light it does not collect light energy.
How much electricity is needed to power an LED?
It really depends on the LED/application. Some, such as those used in instrument panels, can be powered by your standard AA (1.5 volts) battery, while the ones in car lights require much more power. (Car batteries are generally around 12 volts).
How can you make one light bulb change different colors automatically with wiring?
A normal incandescent or fluorescent lamps can not change colors. Even an LED can not change color. But an LED can be designed to have a certain color. Color changing LED is actually a combination of of three LEDs encapsulated in one casing. By turning the LED on or off a combination of colors can be achieved.
How many volts does 3 red led need to light?
6
How many volts does an LED need to light?
That depends on the current. The formula P=IV (where P is power in watts, I is current in amps and V is voltage in volts) is how you calculate the power. So if the current is 2 and the voltage is 3 then P=2x3=6Watts. Use an ammeter to determine the current.
What voltage is led?
A: The voltage for LEDS varies from 1.8v to even 5 volts. These voltages also varies from color to color. A 5 volt LED usually has a tiny resistor in series so the led can be tied across a 5v buss as a unit. Some manufactures actually has two LEDS in series to provide more brightness
How bright is a 3000k led?
It depends on the wattage and how much light the LED emits. 3000K refers to the color temperature of the light and has no relationship to brightness.
Is it hard to repair a color changing led?
It is very simple to repair a color changing LED light on a strand of Christmas lights. You simply pull the damaged light out of the socket and replace it with a new one.
How do you make an led light?
A: LED NEEDS at least 1.8v to light and a current of at least 10ma. Try 2 AAA battery in series and a 70 resistor if it doesn't light it means the voltage must be greater the 1.8v it could 5v volts.
What are the different color spectra of a LED?
A single LED emits light at one single frequency, so it has no spectrum.
How do you make your computer mouse change color?
- make a transparent cover of the mouse, put many colour LED light inside, then through the transparent cover, you can see the mouse cover will change and change colour of the LED light. - make a special rubber mouse case for the mouse. It might be many colours of the case, so that you can change the mouse colour by wrap the rubber cover case.
What is the purpose of a LED in a circuit?
An LED, or light emiting diode, can have many functions. Commonly used as a solid state light emitter, LEDs of nearly any color of light are available, including ultraviolet and infrared.A less obvious use of a light emitting diode is to detect light. A LED makes a very efficent and narrow band light detector. It will produce electric current in response to light that is about the same wavelength (and therefore color) as when it is used as an emitter.Another use of an LED is to make a fairly stable voltage reference; A red LED when forward biased will have a steady voltage drop of about 1.8 volts, an orange LED produces a voltage drop of about 2.0 volts, and about 3.5 volts for blue and white emitting LEDs.LEDs can be used as modulated light emitters to transmit speech, music and digital information. A good example is a television remote control which digitally pulses a infrared LED to change channels, control volume, and so on.LEDs are used in solid state switches when optically coupled to a photodiode or photo resistor. LED flashlights are very common, and some small light bulb replacements are available, with larger bulb replacements soon to come. Some links are provided below:
How does electrical energy change into light energy?
in an led ; in an bulb
Why is a resistor used to operate an LED?
To calculate the current through an LED, use the following formula Current = (Source_voltage - Led_voltage_drop)/Resistance Now if you didn't use a resistor, the you only have the resistance in the wire, which is very small (eg .001 ohm). So if you have for instance a 9V battery, and a 2.1 volt drop across the LED, the resultant current would be so high, it would destroy the LED. We put a resistor in to lower the current to an acceptable range (often 20-30ma)
