Defibrillator

Definition

A defibrillator is a medical device that delivers a dose of electric current to the heart to treat life-threatening cardiac dysrhythmias. It utilizes capacitors to store and release electrical energy quickly.

5 Must Know Facts For Your Next Test

1. Defibrillators use capacitors to store the electrical energy needed for the shock.
2. The energy stored in a capacitor is given by $E = \frac{1}{2}CV^2$, where $C$ is capacitance and $V$ is voltage.
3. Capacitors in defibrillators are designed to release their stored energy rapidly, creating a high-intensity electric pulse.
4. The effectiveness of a defibrillator depends on both the amount of stored energy (in joules) and the rapidity of its discharge.
5. Typical capacitors in defibrillators have large capacitances, often measured in farads, to ensure enough energy can be stored.

Review Questions

• How does a capacitor function within a defibrillator?
• What formula represents the energy stored in a capacitor?
• Why is rapid discharge important for the effectiveness of a defibrillator?

Related terms

Capacitance: The ability of a system to store an electric charge, measured in farads (F).

Electric Current: The flow of electric charge, measured in amperes (A).

Joule: A unit of energy or work in the International System of Units (SI), defined as one newton-meter.