प्रतिक्रिया लेख्दा
*कृपया प्रतिक्रिया लेख्दा सभ्य भाषामा लेख्न अनुरोध छ। * जथाभावी उपनाममा लेखिएका प्रतिक्रियाहरुले स्थान नपाउन सक्छन्। नाम सहितका कमेन्टले प्राथमिकता पाउने छन्। फर्जी नाम, उपनाम लेख्नेको कमेन्ट प्रकाशित नहुन सक्छ। *असभ्य भाषा र धाकधम्की सहितका कमेन्टको आईपी प्रकाशित गर्न सकिनेछ। *हिंसालाई बढावा दिने, विद्वेश फैलाउने र निरंकुशताको पक्षपोषण गर्ने प्रतिक्रियालाई सकेसम्म स्थान दिइने छैन। * प्रतिक्रिया प्रकाशन गर्ने कि नगर्ने भन्ने सम्बन्धमा सबै निर्णय गर्ने अधिकार म आफैमा रहनेछ।
Determine the LED forward voltage. Look at the manufacturer's data sheet and find the specification for the typical forward voltage. This is a close approximation to the voltage across the diode. Alternatively, measure the voltage drop across the LED when it is lit with a voltmeter. Otherwise, just estimate the forward voltage based on the color of the LED. Use 1.8 volts for a red LED, 3.5 volts for a white LED, 3.6 volts for a blue LED and 2.1 volts for a green, orange or yellow LED.
2
Determine the electrical current flowing through the LED. Look at the manufacturer's data sheet and find the typical electrical current associated with the typical forward voltage. This electrical current is a close approximation to the current through the diode. Alternatively, measure the electrical current through the LED with an ammeter if you want an exact value. Otherwise, just roughly estimate that the current through the LED is around 20 milliamperes.
3
Calculate the LED power. Multiply the voltage across the LED by the current through the LED. Use the result obtained in Step 1 for the voltage and the result obtained in Step 2 for the current. For example, for an LED that has typical forward voltage of 2.1 volts with an associated typical current of 20 milliamperes, calculate that the LED power is 42 milliwatts, since 2.1 multiplied by 0.02 is 0.042. Remember that power in watts is equal to current in amperes multiplied by voltage in volts, and that 1000 milliwatts is equal to one watt and 1000 milliamperes is equal to 1 ampere.
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You can also calculate the current and voltage across the LED. This requires that you analyze the electrical circuit that the LED is a part of. If the circuit contains many other electronic components besides the LED, this can become a complex task.
Most electronic circuits with LEDs that have been designed for maximum reliability, have been designed such that the LED has a voltage across it that is near the typical forward voltage specification given by the manufacturer. Because the forward voltage across the LED sets the value of the electrical current through the LED, the power that the LED requires is approximately equal to the forward voltage multiplied by the current at the forward voltage.
When approximating the power, consider that the current through a LED will vary considerably with just a small change in voltage across the LED. Also consider that different LEDs, even though they produce the same color light, will have somewhat different levels of current for the same forward voltage.
काठमाडौ, भदौ २७ (नागरिक) सरकारले विद्यार्थीलाई वर्षमा चार सिलिन्डर ग्यास र १ सय २० लिटर मट्टितेल सहुलियतमा दिने भएको छ। यो सहुलियत असोज १ देखि कार्यान्वयनमा आउनेछ। सरकारले सहुलियत सम्वन्धी प्रस्ताव बुधवारको मन्त्रिपरिषद्बाट निर्णय हुनेछ। वाणिज्य तथा आपूर्ति मन्त्रालयले तयार पारेको यो प्रस्तावलाई प्रधानमन्त्री बाबुराम भट्टराईसँग मंगलबार भएको सहमत भएका थिए। ग्यास प्रयोग गर्ने विद्यार्थीले तीन महिनामा एक सिलिन्डर ग्यासमा २ सय ५० रुपैयाँ छुट पाउनेछन् भने मट्टितेल प्रयोग गर्ने विद्यार्थीको हकमा महिनामा मासिक १० लिटर पाउनेछन्।
विद्यार्थीले मट्टितेल बजार भाउ भन्दा १० रुपैयाँ सस्तोमा पाउनेछन्। 'विद्यार्थीलाई सहुलियतमा ग्यास र मट्टितेल सहुलियतमा दिने प्रस्ताव बुधवारको मन्त्रिपरिषद्मा पेस हुनेछ,' मन्त्रालयका सहसचिव दिपक सुवेदीले नागरिकसँग भने, 'यो राहत दिँदा वार्षिक रुपमा ५० करोड रुपैयाँ दिनुपर्नेछ।' यो सहुलियत सामुदायिक, सरकारी, पब्लिक कलेजका विद्यार्थीले पाउनेछन्। शिक्षा मन्त्रालयका अनुसार ६ लाख यस्ता कलेजमा अध्ययन गर्ने विद्यार्थी ६ लाख रहेका छन्। सुवेदीका अनुसार विद्यार्थीले ग्यास वा मट्टितेल किनेको विल पेस गरेपछि सम्वन्धित कलेजको लेखाशाखाबाट रकम फिर्ता पाउनेछन्। विद्यार्थीले ग्यास वा मट्टितेल किन्दा परल मूल्यमा किन्ने र पछि विल पेस गरेर रकम फिर्ता पाउने उनले बताए। सहुलियत दुरुपयोग भए/ नभएको बारेमा भने शिक्षा मन्त्रालयले अनुगमन गर्ने कार्यविधिमा छ।
