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LDR could mean a long-distance relationship? It would be better to spell out abbreviations in full, as there could be several interpretations. More information is needed.
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What happens to an LDR when a bright light is shined upon it?
When LDR is exposed to light energy . Due to light energy incident on LDR surface, free electron movement of an atom is increased in LDR. This causes high conduction of curent flowing through LDR. beause of free electron movement in LDR, resitance get decreased.
What is a LDR dependent AC dimmer?
The LDR dependent AC dimmer is a Light Dependent Resistor which works by chopping off the parts of the AC voltage.
What is the function of the Light dependent resistor?
The resistance of LDR increases when light is not available (or is limited). And the resistance drops when Light is abundant.This principle can be used in proximity detectors where one or more light source(s) is/are active. When a person / object comes in proximity of the source, the light gets reflected from the object-surface & can now be received by LDR. So due to proximity of the object, resistance of LDR changes - this can be used to trigger different actions like open the door, trigger a motor. Fire an alarm. etc.Resistance of LDR varies according to intensity of incident light over it,It is used in street light to detect day/night and turn on/off the street light automatically
How do you make Light-dependent- resistance circuit?
A Light Dependent Resistor (aka LDR, photoconductor, or photocell) is a device which has a resistance which varies according to the amount of light falling on its surface.A typical light dependent resistor is pictured above together with (on the right hand side) its circuit diagram symbol. Different LDR's have different specifications, however the LDR's we sell in the REUK Shop are fairly standard and have a resistance in total darkness of 1 MOhm, and a resistance of a couple of kOhm in bright light (10-20kOhm @ 10 lux, 2-4kOhm @ 100 lux).Uses for Light Dependent ResistorsLight dependent resistors are a vital component in any electric circuit which is to be turned on and off automatically according to the level of ambient light - for example, solar powered garden lights, and night security lighting. An LDR can even be used in a simple remote control circuit using the backlight of a mobile phone to turn on a device - call the mobile from anywhere in the world, it lights up the LDR, and lighting (or a garden sprinkler) can be turned on remotely!Light Dependent Resistor CircuitsThere are two basic circuits using light dependent resistors- the first is activated by darkness, the second is activated by light. The two circuits are very similar and just require an LDR, some standard resistors, a variable resistor (aka potentiometer), and any small signal transistor In the circuit diagram above, the LED lights up whenever the LDR is in darkness. The 10K variable resistor is used to fine-tune the level of darkness required before the LED lights up. The 10K standard resistor can be changed as required to achieve the desired effect, although any replacement must be at least 1Kto protect the transistor from being damaged by excessive current.By swapping the LDR over with the 10K and 10K variable resistors (as shown above), the circuit will be activated instead by light. Whenever sufficient light falls on the LDR (manually fine-tuned using the 10K variable resistor), the LED will light up.Using an LDR in the Real WorldThe circuits shown above are not practically useful. In a real world circuit, the LED (and resistor) between the positive voltage input (Vin) and the collector (C) of the transistor would be replaced with the device to be powered. Typically a relay is used - particularly when the low voltage light detecting circuit is used to switch on (or off) a 240V mains powered device. A diagram of that part of the circuit is shown above. When darkness falls (if the LDR circuit is configured that way around), the relay is triggered and the 240V device - for example a security light - switches on.NEW For details of a more advanced light/dark sensor circuit click here to read our new article LM741 Light/Dark Sensor Circuit. We have these circuits available for sale.
What household objects have LDR circuits in them?
Typically anything that can turn on/off with ambient light detection (night lights, solar landscaping lights, laptops with lighting sensor to adjust the brightness and keyboard backlights, mobile phones, etc..)
What is the type of ldr commonly used in schools?
automatic
Why LDR used in PIR sensor?
industrial automaton
What is the symbol for ldr?
this is the symbol for ldr
What is an LDR symbol?
An LDR is a Light dependent resistor.
What type of LDR commonly used in schools?
Basically, ETC
What is the meaning of LDR?
LDR refers to Light Dependent Resistor.
How does light affect LDR?
An LDR is a light dependent resistor, which is usually used to detect light levels, either ambient or reflected. The LDR works because incoming light carries energy, which can elevate the energy levels of electrons in a suitable medium to join the 'conduction band' which means that there are more charge carriers in the LDR, and hence the cell has lower resistance.
What does LDR stand for?
Light Dependent Resistor LDR also means long distance relationship.
What is the symbol for LDR Holding Corporation in NASDAQ?
The symbol for LDR Holding Corporation in NASDAQ is: LDRH.
Which material is used in LDR?
Cadmium Sulphide (CdS), Cadmium Selenide (CdSe), Selenium, etc.
In what year did LDR Holding Corporation - LDRH - have its IPO?
LDR Holding Corporation (LDRH) had its IPO in 2013.
What happens to an LDR when a bright light is shined upon it?
When LDR is exposed to light energy . Due to light energy incident on LDR surface, free electron movement of an atom is increased in LDR. This causes high conduction of curent flowing through LDR. beause of free electron movement in LDR, resitance get decreased.
