The air can withstand an electric field of about 3.0 x 106 V/m before electrons will be split from molecules of air, creating an electrical discharge. If you place your fingertip 1.0 millimeter away from a doorknob, and a static discharge of .55 mA lasting for .010 seconds occurs, what is the capacitance of your fingertip one mm away from a doorknob?

73.0-m length of coaxial cable has an inner conductor that has a diameter of 2.58 mm and carries a charge of 8.10 µC. The surrounding conductor has an inner diameter of 7.27 mm and a charge of −8.10 µC. Assume the region between the conductors is air. (a) What is the capacitance of this cable?C =  nF(b) What is the potential difference between the two conductors?ΔV =  kV

A capacitor has a voltage difference between its terminals of 1.3 V. The amount of charge stored in the capacitor is 16 uC. What is the capacitance of the capacitor?

An engineer connects a 24.0 V battery to a capacitor of unknown capacitance. The result is that 52.0 µC of charge is stored on the capacitor. How much energy (in J) is stored in the capacitor?

A negatively charged particle of mass 4.30 x 10-19 kg is moving with a speed of 35.0 m/s when it enters the region between two parallel capacitor plates. The initial velocity of the charge is parallel to the plate surfaces and in the positive x-direction. The plates are square with a side of 1.00 cm, and the voltage across the plates is 2.50 V. If the particle is initially 1.00 mm from both plates and it just barely clears the positive plate after traveling 1.00 cm through the region between the plates, how many excess electrons are on the particle? Ignore gravitational and edge effects. 35.0 m/s 2.00 mm 1.00 cm Numeric Response

The dielectric constant of a solid is 2000. It is placed between the plates of a capacitor that are 1 μm apart and with an applied voltage of 0.10 V. Calculate the capacitance per square millimetre of this device and the local electric field acting on an atom in the dielectric.

A parallel‑plate capacitor has square plates that have an edge length equal to 9.00×102 cm and are separated by 8.00 mm. It is connected to a battery and is charged to 12.0 V. How much energy ?electric is stored in the capacitor?

A student is trying to build a home-made capacitor. He uses two 1.0 cm x 1.0 cm aluminum foil as the two parallel conducting plates, spaced 0.40 cm apart. He then connects the two foils with a 3.0 V battery. How many electrons are stored in the negative plate?

The plates of a spherical capacitor have radii 35.7 mm and 37.8 mm. (a) Calculate the capacitance. (b) What must be the plate area of a parallel-plate capacitor with the same plate separation and capacitance? (a) Number i Units (b) Number i Units

Two identical capacitors Ca and Cb each of capacitance 2.70 μF are connected in parallel across a CONSTANT total electric potential difference of 510 V. A dielectric slab of dielectric constant 6.90 can fill Ca and is slowly inserted into that capacitor.What is the change in charge, ΔQa, on Ca when the dielectric is added to Ca?