Physics equations/18-Electric charge and field/Q:findE/More practice

B
{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? +a) 8.02 x 10-1N/C -b) 9.26 x 10-1N/C -c) 1.07 x 100N/C -d) 1.23 x 100N/C -e) 1.43 x 100N/C
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{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? -a) 4.15 x 101degrees -b) 4.8 x 101degrees -c) 5.54 x 101degrees -d) 6.4 x 101degrees +e) 7.39 x 101degrees
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{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/a2, where β equals -a) 4.1 x 10-3 -b) 4.96 x 10-3 -c) 6.01 x 10-3 +d) 7.28 x 10-3 -e) 8.82 x 10-3
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{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/a2, where β equals -a) 1.61 x 10-1 -b) 1.95 x 10-1 -c) 2.36 x 10-1 -d) 2.86 x 10-1 +e) 3.47 x 10-1
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