1. A 100 nC charge is placed at the origin. A -50 nC charge is placed at x= 5 cm and a 200 nC is placed at x= -10 cm.

a. What is the net electrostatic force acting on 200 nC charge?

2. Three positively charged spheres, each with a charge of 4.0 x 10 ^-6 C, are fixed at the vertices of an equilateral triangle whose sides are 20 cm long. Calculate the magnitude of the net electrostatic force on the third charge.

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