1 What is the magnitude of the electric field at the origin if a 2.9 nC charge is placed at x = 5.9 m, and a 2.7 nC charge is placed at y = 9.2 m?

2 What angle does the electric field at the origin make with the x-axis if a 1.3 nC charge is placed at x = -9 m, and a 1.5 nC charge is placed at y = -5.2 m?

3 A dipole at the origin consists of charge Q placed at x = 0.5a, and charge of -Q placed at x = -0.5a. The absolute value of the x component of the electric field at (x,y) =( 4a, 3a) is βkQ/a^{2}, where β equals

4 A dipole at the origin consists of charge Q placed at x = 0.5a, and charge of -Q placed at x = -0.5a. The absolute value of the y component of the electric field at (x,y) =( 1.1a, 1.2a) is βkQ/a^{2}, where β equals