Physics Electrostatics Level: University
Energy of CapacitorA lightning flash transfers 4.08 C of charge and 3.03 MJ of energy to the Earth. Between what potential difference did it travel?
Physics Electrostatics Level: University
CapacitorConsider the earth and a cloud layer 840 m above the Earth to be the plates of a parallel-plate capacitor. Assume that the cloud layer has an area of 1.14 km^2 = 1.14 X 10^6 m^2. If an electric field strength greater than 3.27 X 10^6 V/m causes the air to break down and conduct charge ( lightning) What is the maximum charge the cloud can hold?
Physics Electrostatics Level: University
Potential and field intensityConsider an electron between the plates of a charged capacitor.The figure below shows a situation where the potential difference across the capacitor (V) and the separation between the capacitor plates (d) vary, The values for six specific situations are given below.
Rank them in order of increasing magnitude of the force felt by the electron from smallest to largest
(If B is smallest then A C D and finally E is largest enter BACDE)
( Note: If of equal magnitude then enter in the order listed)
A. d = 3m V= 100 volts
B. d = 3m V = 60 volts
C. d = 4.5m V = 90 volts
D. d = 4.5m V = 150 volts
E. d = 3m V = 60 volts
F. d = 3.5m V = 100 volts
Physics Electrostatics Level: University
Potential EnergyCalculate the speed of (a) a proton and (b) an electron after each particle accelerates from rest through potential difference of 190V.
Physics Electrostatics Level: University
PotentialThe electric potential of a system as a function of position along the axis is given in figure 20-22. (a) In which of the regions 1,2,3 or 4 do you expect E sub x to be greatest. In which region does E sub x have its greatest magnitude .Explain. (b)Calculate the value of E sub x in each of the three regions 1, 2, 3, and 4 .
Physics Electrostatics Level: University
PotentialA typical 12-V car battery can deliver 7.5 x 10 to the 5th C of charge. If the energy supplied by the battery could be converted entirely to kinetic energy. What speed would it give to a 1200-kg car.
Physics Electrostatics Level: University
PotentialThe earth has an electric field with a magnitude of approximatly 100v/m near its surface. What is the potential difference between a point on the ground and a point on the same level as the top of the Washington Monument (555 ft high)
Physics Electrostatics Level: University
CapacitorNerve cells are long, thin cylinders along which electrical disturbances ( never impulses) travel. The cell membrane of a typical nerve cell consists of an inner and outer well separated by a distance of. 10 um. The electric field within the cell membrane is 7.0 x 10 to 5th N/C. Approximating the cell membrane as a parallel- plate capacitor determine the magnitude of the charge density on the inner and outer cell walls.
Physics Electrostatics Level: University
CapacitorA parallel plate capacitor is constructed with circular plates of radius 0.750 cm and plate separation 0.0500 mm. If the capacitor is connected across a 37.2V source find.
(a) The capacitance.
(b) The surface charge in each plate.
(c) The energy stored in the capacitor.
(d) The electric field between plates.
(e) If a slab of plastic with dielectric constant K = 3.6 is inserted between the plates of the capacitor What will the capacitance be?
Physics Electrostatics Level: University
Coulombs LawThree charges lie along the x-axis. The positive charge q1 = 15 uC is at x = 2M and a positive charge q2 = 6 uC is at the origin. Where must a negative charge q3 be placed on the x-axis so that the resultant force will be 0? (Answer 0.78m)
Physics Electrostatics Level: University
Coulombs LawThree equal charges of +6 uC are spaced along a line. The end charges are 2 m from the central charge. What are the magnitude and direction of the force on each charge.
Physics Electrostatics Level: University
Electric fieldSketch the electric field lines for the system of charges shown in 19-32
Physics Electrostatics Level: University
Figure 19 - 32 shows a system consisting of three charges q1 = +5.oo uC q2 = +5.00 uC and q3 = + 5.00 uC at the verticces of an equilateral traingle of side d=2.75 cm. (a) Find the magnitude of the electric field at a point halfway between the charges q1 and q2. (b) Is the magnitude of the electric field halfway between the charges q2 and q3 greater than less than or the same as the electric field found in fart (a) explain. (c) Find the magnitude of the elctric field at the point specified in part(b).
Physics Electrostatics Level: University
Principle of super positionThe point charges in 19-32 have the following values q1 = 2.1uC q2 = + 6.3 uC q3 = -89 uC. (a) Given that the distance d in figure 19 - 32 is 4.35 cm, Find the direction and magnitude of the net electrostatic force exerted on the point charge q1. (b) How would your answer to part (a) change of the distance d were doubled explain
Physics Electrostatics Level: University
Two pont charges lie on the x axis.A charge of + 9.9 uC is at the origin and a charge of -5.1 uC is at x = 10.0cm (a) At what position x would a third charge q3 be in equilibrium. (b) Does your answer to part (a) Depened on whether q3 is positive or negative, Explain.