Practice: A cardiac defibrillator can be modeled as a parallel plate capacitor. When it is charged to a voltage of 2 kV, it has a stored energy of 1 kJ. What is the capacitance of the defibrillator?

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Capacitors & Capacitance | 8 mins | 0 completed | Learn |

Parallel Plate Capacitors | 20 mins | 0 completed | Learn Summary |

Energy Stored by Capacitor | 16 mins | 0 completed | Learn |

Capacitance Using Calculus | 8 mins | 0 completed | Learn |

Combining Capacitors in Series & Parallel | 16 mins | 0 completed | Learn |

Solving Capacitor Circuits | 29 mins | 0 completed | Learn |

Intro To Dielectrics | 18 mins | 0 completed | Learn Summary |

How Dielectrics Work | 3 mins | 0 completed | Learn |

Dielectric Breakdown | 5 mins | 0 completed | Learn |

Concept #1: Energy Stored by Capacitor

That should be 10^{−6} m^{3}, not just meters. (The number's right, the exponent on the unit is missing.)

Practice: A cardiac defibrillator can be modeled as a parallel plate capacitor. When it is charged to a voltage of 2 kV, it has a stored energy of 1 kJ. What is the capacitance of the defibrillator?

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Concept #1: Energy Stored by Capacitor

Practice #1: Capacitance of Defibrillator

Example #1: Energy Released by Flashbulb

A 4-μF capacitor has a potential drop of 20 V between its plates. The electric potential energy stored in this capacitor is:
A) 80 μJ
B) 8 μJ
C) 8000 μJ
D) 800 μJ

A parallel-plate capacitor is connected to a battery and allowed to charge up. Now the battery is disconnected from the capacitor. The separation between the two plates is now decreased (the plates get closer together). What can we say about the potential energy stored by the capacitor?
A) The potential energy increases
B) The potential energy decreases
C) The potential energy remains the same
D) Unable to determine from the information given.

A 4-μF capacitor has a potential drop of 20 V between its plates. The electric potential energy stored in this capacitor is:
A) 8 μJ
B) 8000 μJ
C) 80 μJ
D) 800 μJ

In open-heart surgery a small amount of energy will defibrillate the heart.(a) What voltage is applied to the 8.59 μF capacitor of a heart defibrillator that stores 44.8 J of energy? ________KV (b) Find the amount of stored charge. ________mC

Suppose a parallel plate capacitor (with capacitance C0) is fully charged (to a value Q0) by a battery. The battery (which supplies a potential difference of V0) stays connected to the capacitor. If the plates of the capacitor are then moved closer together (the separation distance d between the plates is halved), describe quantitatively what happens to: a) the capacitance of the capacitor. b) the potential difference between the plates. c) the energy stored in the capacitor. d) the charge on the plates.

Two 3.00 cm × 3.00 cm plates that form a parallel-plate capacitor are charged to± 0.708 nCA)What is the electric field strength inside the capacitor if the spacing between the plates is 2.60 mm ?Express your answer with the appropriate units.B)What is the potential difference across the capacitor if the spacing between the plates is 2.60 mm ?Express your answer with the appropriate units.

Two 3.00 cm × 3.00 cm plates that form a parallel-plate capacitor are charged to ± 0.708 nCA) What is the electric field strength inside the capacitor if the spacing between the plates is 1.30 mm ? Express your answer with the appropriate units.B) What is potential difference across the capacitor if the spacing between the plates is 1.30 mm ?Express your answer with the appropriate units.

Consider the case when the constant A = 3 and the time constant, τ = 4. Plot the graph of y = 3e-t/4. Make it a position versus time graph.

Storm clouds build up large negative charges, as described in the chapter. The charges dwell in charge centers, regions of concentrated charge. Suppose a cloud has -25 C in a 1.0-km-diameter spherical charge center located 10 km above the ground, as sketched in the figure. The negative charge center attracts a similar amount of positive charge that is spread out on the ground below the cloud.The charge center and the ground function as a charged capacitor, with a potential difference of approximately 4 x 108 m The large electric field between these two "electrodes" may ionize the air, leading to a conducting path between the cloud and the ground. Charges will flow along this conducting path, causing a discharge of the capacitor - a lightning strike.1) What is the approximate magnitude of the electric field between the charge center and the ground?A) 4 x 104 V/m B) 4 x 105 V/mC) 4 x 106 V/m D) 4 x 107 V/m2) What is the approximate capacitance of the charge center-ground system?A) 6 x 10-8 FB) 2 x 107 FC) 4 x 106 FD) 8 x 106 F3) If the cloud transfers all of its charge to the ground via several rapid lightning flashes lasting a total of 1.90 s, what is the average power?A) 12.7 GWB) 3.74 GWC) 2.74 GWD) 1.74 GW

Capacitor 2 has half the capacitance and twice the potential difference as capacitor 1. What is the ratio Uc1/Uc2.

Part A. Find the energy U0 stored in the capacitor. Express your answer in terms of A, d, V, and ϵ0.Part B. The capacitor is now disconnected from the battery, and the plates of the capacitor are then slowly pulled apart until the separation reaches 3d. Find the new energy U1 of the capacitor after this process.Express your answer in terms of A, d, V, and ϵ0.Part C. The capacitor is now reconnected to the battery, and the plate separation is restored to d. A dielectric plate is slowly moved into the capacitor until the entire space between the plates is filled. Find the energy U2 of the dielectric-filled capacitor. The capacitor remains connected to the battery. The dielectric constant is K.Express your answer in terms of A, d, V, K, and ϵ0.

In open-heart surgery, a small amount of energy will defibrillate the heart. (a) What voltage is applied to the 8.28 μF capacitor of a heart defibrillator that stores 42.3 J of energy? _________ kV(b) Find the amount of stored charge._________ mC

A capacitor consists of two 7.0-cm-diameter circular plates separated by 1.0 mm. The plates are charged to 160 V , then the battery is removed.1) How much energy is stored in the capacitor?2) How much work must be done to pull the plates apart to where the distance between them is 2.0 mm?

You have two capacitors, one is 6.0 μF the other is 3.0 μF. You also have some wires and a 9.0 V battery. Determine the total energy stored by the capacitors when a) Connected in parallel and b) connected in series. Which configuration has greater energy?

Suppose you have a 9.00-V battery, a 2.00-μF capacitor, and a 7.40-μF capacitor Find the charge and energy stored if the capacitors are connected to the battery in parallel

Suppose you have a 9.00-V battery, a 2.00-μF capacitor, and a 7.40-μF capacitor Find the charge and energy stored if the capacitors are connected to the battery in series. .

A pair of 10μF capacitors in a high-power laser are charged to 1.7 kV.a. What charge is stored in each capacitor?b. How much energy is stored in each capacitor?

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