Physics Electrostatics Level: High School
What capacitance is required to store an energy of 11 kW-h at a potential difference of 1200 V ?
Physics Electrostatics Level: High School
An air-filled parallel-plate capacitor has a capacitance of 1.4 pF. The separation of the plates is doubled and wax is inserted between them . The new capacitance is 2.4 pF. Find the dielectric constant of the wax
Physics Electrostatics Level: High School
A 2.9 micro F capacitor and a 4.4 micro F capacitor are connected in parallel across a 330 V potential difference . Calculate the total energy in joules stored in the capacitors .
Physics Electrostatics Level: High School
Hydrogen atom is a single electron revolves around a single proton in a circle of radius r, assume proton is at resta) by equating the electrical force to the electron mass times is acceleration, derive an expression for the electrons speed .
b) Obtain an expression for the electrons kinetic energy and show that its magnitude is just half of the electrical potential energy .
c) Obtain an expression for the total energy and evaluate it using r = 5.29*10^-11m . Give your numerical results in Joules and electron volts .
Physics Electrostatics Level: High School
A potential difference of 800 V is established between two parallel plates 3cm apart an electron is released from the negative plate at the same instant a proton is released from the positive plate .a) How far from the positive plate will they pass each other ?
b) What is the ratio of their speeds when they strike the opposite plate ?
c) What is the ratio of their kinetic energies when they strike the opposite plates ?
Physics Electrostatics Level: High School
Some cell walls in the human body have a double layer of surface charge with a layer of negative charge inside and a layer of positive charge of equal magnitude on the other. Consider a model for such a cell in which surface charge densities are + or – 5*10^-3 and the cell wall is 5.0*10^-9 m thick (Note use using parallel plates)a) Find the electric field magnitude in the wall between the two charge layers
b) The potential difference between inside and outside the cell . Which is the higher potential.
Physics Electrostatics Level: High School
A positive charge +q is located at the point (x = 0, y = -a) and an equal charge –q is located at point (x = 0, y = +a)a) Draw a diagram showing positions of the charges.
b) What is the potential at a point on the x axis distance x from origin .
c) Derive an expression for the potential at a point on the y-axis a distance y from the origin.
d)sketch a graph of the potential at points on the y-axis as a function of y in the range of y = -4a to y = +4a . Plot positive potentials upward and negative potential downward .
Physics Electrostatics Level: High School
An uncharged 5.0 micro F capacitor and a resistor are connected in series to a 12-V battery and an open switch to form a simple RC circuit. The switch is closed at t = 0 s . The time constant of the circuit is 4.0 s . Determine the maximum charge on the capacitor .a) 6.0 x 10^-5 C
b) 9.5 x 10^-5 C
c) 1.5 x 10^-5 C
d) 4.8 x 10^-5 C
e) 5.5 x 10^-5 C
Physics Electrostatics Level: High School
Three parallel plate capacitors , each having a capacitance of 1.0 micro F are connected in parallel . The potential difference across the combination is 100 V . What is the charge on any one of the capacitors .a) 30 micro C
b) 100 micro C
c) 300 micro C
d) 1000 micro C
e) 3000 micro C
Physics Electrostatics Level: High School
A parallel plate capacitor has a potential difference between its plates of 1.2 V and a plate separation distance of 2.0 mm . What is the magnitude of the electric field if a material that has a dielectric constant of 3.3 is inserted between the plates ?a) 75 V/m
b) 180 V/m
c) 250 V/m
d) 400 V/m
e) 500 V/m
Physics Electrostatics Level: High School
A charge is located at the center of sphere A (radius RA = 0.0010 m ) . which is in the center of sphere B (radius RB = 0.0012 m) . Spheres A and B are both equipotential surfaces . What is the ratio VA/VB for the potential of these surfaces ?a) 0.42
b) 0.83
c) 1.2
d) 1.4
e) 2.4
Physics Electrostatics Level: High School
If the work required to move a +0.35 C charge from point A to point B is +125 J , what is the potential difference between the two points ?a) zero volts.
b) 44 V
c) 88 V
d) 180 V
e) 360 V
Physics Electrostatics Level: High School
Two point charges are arranged along the x axis as shown in the figure at ‘click here’ . At which of the following values of x is the electric potential equal to zero ? Note : At infinity, the electric potential is zero .a) +0.05 m
b) +0.29 m
c) +0.40 m
d) +0.54 m
e) +0.71 m
Physics Electrostatics Level: High School
Two positive point charges are separated by a distance R. If the distance between the charges is reduced to R/2, what happen to the total electric potential energy of the system ?a) It is doubled
b) It remains the same
c) It increase by a factor of 4
d) It is reduced to one-half of its original value
e) It is reduced to one-fourth of its original value
Physics Electrostatics Level: High School
which one of the following statements best explains why it is possible to define an electrostatic potential in a region of space that contains an electrostatic field ?a) Work must be done to bring two positive charges closer together .
b) Like charges repel one another and unlike charges attract one another
c) A positive charge will gain kinetic energy as it approaches a negative charge .
d) The work required to bring two charges together is independent of the path taken .
e) A negative charge will gain kinetic energy as it moves away from another negative charge .