How much energy does the battery deliver in this 80 h interval? - how much doesmag-5 laser cost
The manufacturer of dry cell 9V battery, said battery providing 20 mA for 80 hours continuously. Meanwhile, the voltage from 9 am to 6 V is reduced. Suppose that the voltage drop is linear with time. What is the battery a lot of light in this interval of 80 hours?
Saturday, January 30, 2010
How Much Doesmag-5 Laser Cost How Much Energy Does The Battery Deliver In This 80 H Interval?
1 comment:
If it is linear, then we can average the voltage to 7.5 volts, while the drain current is constant. When power is not constant, you need the calculation.
7.5vx 20 mA = 150 mW
80 hours 288,000 seconds
Power 150 mW x 288,000 = s = 43200 joules, or 12 watt-hours
.
Post a Comment