How many hours LED burn

[John1397]

How many hours will a 20ma led burn on a AA battery rated at 700?

John

[Geek-9pm]

Is this homework?

The battery is not rated for constant drain. The book says that it normally is used only a few hours each day.

Read you assignment carefully. The 700 bis 700 milliamp hours.
That can mean either 700 milliamps for one hour, or one milliamp for 700 hours. It is a product.

Milliamp Hours.
http://en.wikipedia.org/wiki/Ampere-hour
From the above link you can deduce that Milli Amp hour is the product of milliamps multiplied by the number of hours the battery can last in intermittent service.

[madcaddies]

dunno much about led technology but one product i have claims 50k hours of operating time before burning out.

[patio]

dunno much about led technology but one product i have claims 50k hours of operating time before burning out.

On what power source ? ?
It was a 2 part query...