A test charge of + 4 μC is at a field-point P where the electric field E due to other charges is directed to the right and has a magnitude ∣E∣ = 4 x 106 N/C. If the test charge is replaced with a charge of - 4 μC, the electric field at P gets modified to E' as :

The magnitude of electric field is 1750 N/C at a distance 145 x 10-3 m from this sphere of radius 355x 10-3 m. Find the charge density within it.

Charge Q is uniformly distributed in a sphere of radius R. (a) What fraction of the charge is contained within radius r-0.207R? (b) What is the ratio of the electric field magnitude at r= 0.207R to that on the surface of the sphere? (a) Number Units (b) Number Units

Find the electric field at the location of qa in the figure given that qb = qc = qd = +2.00 mC, q = -1.00 nC, and the square is 20.0 cm on a side. a) Calculare the electric field at qa due to q and qd (add the fields due to those two charges together). Give a positive value if the field is in the second quadrant, and negative if it is in the fourth quadrant. b) Now calculate the field due to qb and qc. Add the fields together, remembering that they are vectors. GIve a positive value for 2nd quadrant, negative for 4th.

A square plate of copper with 55.0 cm sides has no net charge and is placed in a region of uniform electric field of 75.0 kN/C directed perpendicularly to the plate. (a) Find the charge density of each face of the plate. |nC/m² nC/m? (b) Find the total charge on each face. nC nC

A charge Q1=9 uC is place on the y axis at -3 m, and charge Q2=-16uC is place at the x axis at 4m. What is the magnitude of the net electric field at the origin

The entire y axis is covered with a uniform linear charge density 3.6 nC/m. Determine the magnitude of the electric field on the x axis at x=9.6m

(a) Determine the electric field strength at a point 1.00 cm to the left of the middle charge shown in the figure below. (Enter the magnitude of the electric field only.) Three charges lie along a horizontal line. A 6.00 µC positive charge is on the left. 3.00 cm to its right is a 1.50 µC positive charge. 2.00 cm to the right of the 1.50 µC charge is a −2.00 µC charge.  N/C(b) If a charge of −2.10 µC is placed at this point, what are the magnitude and direction of the force on it? magnitude      N direction

A penny is in an external electric field of magnitude 2.5 kN/C directed perpendicular to its faces. (a) Find the charge density on each face of the penny, assuming the faces are planes. nc/m2 (b) If the radius of the penny is 1 cm, find the total charge on one face. pC

Charge is distributed uniformly throughout the volume of an infinitely long cylinder of radius R = 3.00×10-2 m. The charge density is 4.00×10-2 C/ m3. a)What is the electric field at r = 1.50×10-2 m?  b)What is the electric field at r = 6.00×10-2 m?