Four charges +5 μC , +6 μC, -3 μC and +2 μC are located respectively at the corners A, B, C and D of a rectangle of sides 30 and 40 cm. (a) Calculate the magnitude and direction of the net electric field at the centre of the rectangle. (b) What will be the net electric force on a charge +1.5 µC placed at the centre?

The cockroach Periplaneta americana can detect a static electric field of magnitude 6.00 kN/C using their long antennae. If the excess static charge on a cockroach is modeled as point charges located at the end of each antenna, what magnitude of charge q would each antenna possess in order for each antennae to experience a force of magnitude 5.50 µN from the external electric field? Calculate q in units of nanocoulombs (nC). q= nC

The figure below shows a small, charged bead, with a charge of q = +41.0 nC, that moves a distance of d = 0.174 m from point A to point B in the presence of a uniform electric field  E  of magnitude 255 N/C, pointing right. A positive point charge q is initially at point A, then moves a distance d to the right to point B. Electric field vector E points to the right. (a) What is the magnitude (in N) and direction of the electric force on the bead? magnitude Ndirection     (b) What is the work (in J) done on the bead by the electric force as it moves from A to B?  J (c) What is the change of the electric potential energy (in J) as the bead moves from A to B? (The system consists of the bead and all its surroundings.) PEB − PEA =  J (d) What is the potential difference (in V) between A and B? VB − VA =  V

Two charges are located in the x-y plane. If q1 -3.50 nC and is located at (x = 0.00 m, y = 0.960 m), and the second charge has magnitude of q2 = 4.80 nC and is located at (x = 1.40 m, y 0.650 m), calculate the x and y components, Ex and Ey, of the electric field, É, in component form at the origin, (0, 0). The Coulomb force constant is 1/ (4reo) = 8.99 x 10° N · m²/C². -13.58 -40.45 Ex N/C Ey N/C Incorrect Incorrect II