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hey how do i work out how many led's i can hook up to a 9v battery that will last at least a day? Answered

i want to link together as many blue led's on one circuit as i can i was thinking a couple of 9v batteries and a bunch of led's together, but i dont know much about led's :)




10 years ago

ty all :) ive been reading up loads on led's think ive got a good setup sorted, ill tell ya if it all goes wrong haha


10 years ago

volts*amps=watts so a 9 volt is 9*0.595=5.355 watt hours =~0.2 watts per hour for 24 hours so you want an led that will run at ~0.2 watts if you have a bigger led you could change the resistor.

two questions
1. what led do you have?
2. is the nine volt alkaline?