You'll need an external power source (such as a battery charger or another car hooked to battery cables) in order to start your vehicle. A battery which is truly depleted - not just discharged - will not take a charge from the alternator, and will need to be replaced.
No, your battery supplies power to the starter. However if your alternator is defective then it will not supply power to the battery and the battery will soon be depleted.
The car will then be unable to start.
Your car lost power while you were driving and it will not start now because the battery is depleted.
The electrical energy provides power. When the chemical energy is depleted, the battery will not longer generate electrical energy.
A battery that has lost it's charge.
it will arch out and melt the knobs on your battery and your cables
Nothing. The battery is sealed an no harm will be done.
THE BATTERY WILL GO DEAD
they have to be recycled and they wont work.
You will shorten the life of the battery. Only add Distilled water to a battery.
CD player stereos do use a car's battery in about 15 hours. In reality, a car battery shouldn't be depleted by more than 20% as they are designed for high-current, short loads for the starter motor and to be kept charged up.
get a new car