A piece of metal (something metallic) may have rested against the pole (positive and negative) and caused the battery to rapidly drain - heating it up in the process.
It heats up very hot and may explode.
No
This is not advised! The 9-volt charger might have a current limiter so that nothing burns up, but it any case if left on it will destroy the 6 volt battery by overcharging. A 6-volt charger is not expensive.
No, the battery will be overcharged and battery damage will occur if it is done.
No, a lead acid battery is a wet cell battery and a 9 volt alkaline battery is a dry cell battery.
no
A 9 volt battery is stronger than a 1.5 volt battery because it has a higher voltage. The higher voltage allows the 9 volt battery to power more demanding devices and last longer than a 1.5 volt battery.
1.3cm
a 9 volt battery
buy a battery charger
it operates a battery,mostly a 9 volt battery
One is 9 volts and the other is 12 volts. They do not interchange!