Willy Nilly has a battery that is completely discharged. The battery is rated at 80 ampere hours. He has a power supply that he is trying to use to charge the battery, and he has connected to power suppy across the battery. The power supply has an ammeter that measures how much current is being drawn from the supply, and the current drawn is 10 amperes.
The problem Willy has is that the power supply overheats when 10 amperes is drawn from it, and a thermal relay shuts it off. Willy has times the sequence, and he sees that the supply stays on for 3 minutes, then the thermal relay turns off the supply and it takes 2 minutes to cool down. Then the supply comes back on for 3 minutes, off for 2 minutes, etc.
How long will it take to charge the battery?
Willy has also noticed that the power supply has a current limit that can be set. When he sets the current limit to 8 amperes, it provides exactly 8 amperes, but it doesn't overheat, so it's not shutting off all the time.
Should Willy set the current limit to 8 amperes?