Final answer:
Defibrillators use a capacitor to deliver electrical current to the heart, with adjustable energy settings such as '400 joules'. There are two types of defibrillator waveforms: biphasic, which uses less energy, and monophasic, which typically requires higher energy. In open heart surgery, a smaller amount of energy is used for defibrillation.
Step-by-step explanation:
Defibrillators are medical devices used to deliver an electrical current to the heart in order to restore a normal heart rhythm. The energy administered by a defibrillator is stored in a capacitor and can be set according to the specific medical scenario.
There are two main types of defibrillation waveforms: biphasic and monophasic. Biphasic defibrillators deliver current in two phases, reversing polarity mid-way, often allowing for lower energy levels to be used. Monophasic defibrillators deliver current in a single phase, generally using higher energy levels. For instance, phrases like 'make it 400 joules this time' refer to the amount of energy in joules that the defibrillator is set to administer.
Capacitors are also used in other applications such as microelectronics to supply power when batteries are being charged, and in the storage of energy for camera flash lamps. In the context of open heart surgery, reduced energy is used in defibrillation.
A capacitor with 8.00 µF (microfarads) storing 40.0 J (joules) of energy would have a specific voltage and stored charge, which could be calculated using the formula for the energy stored in a capacitor.