Final answer:
The original 'portable' defibrillator was powered by 1 12 V car battery. These devices used a car battery for portability and relied on a capacitor to store and deliver the required electric energy to the heart in joules. Option 3) 1 12 V car battery is the correct answer.
Step-by-step explanation:
The original 'portable' defibrillator was an important advancement in medical technology. It was designed to save lives by restoring a normal heartbeat by delivering a controlled electric shock to the heart. The correct answer to the question about what powered the original portable defibrillator is: 3) 1 12 V car battery. This means that the first portable defibrillators were not as portable as we might consider devices today, but at the time, using a car battery made them mobile enough to be brought directly to a patient in need.
Defibrillators function by delivering a dose of electric current to the heart. The energy required for this process is stored in a capacitor, which is then released to the heart, with the aim of resetting the cardiac rhythm to a normal state. The amount of energy can be adjusted depending on the situation, using SI units of joules. The capacitor's energy, often previously charged by batteries, acts as the source of this life-saving intervention.