Three particles are held in place along the X-axis. One particle has a charge of 25 uCand is located at the origin. Another particle (with a charge of 30 uC) is located at x=10 cm. The last charge is located at ×=-15 cm. What must be the amount of charge on the third particle, if the charge located at the origin is in equilibrium (i.e. all the forces cancel)?

Two point charges are fixed on the y axis: a negative point charge q1 = - 28 μC at y1 = + 0.15 m and a positive point charge q2 at y2 = + 0.35 m. A third point charge q = + 9.2 μC is fixed at the origin. The net electrostatic force exerted on the charge q by the other two charges has a magnitude of 23 N and points in the +y direction. Determine the magnitude of q2.

Three charged marbles are glued to a nonconducting surface and are placed in the diagram as shown. The charges of each marble are q1 = 6.20 µC, q2 = 1.43 µC, and q3 = −2.01 µC. Marble q1 is a distance r1 = 3.00 cm to the left of the marble q2, while marble q3 is a distance r3 = 2.00 cm to the right of the marble q2. Calculate the magnitude of the electric field a distance r' = 1.00 cm to the left of the center marble.N/C Another marble is placed 1 cm to the left of the middle marble. If this new marble has a charge of  3.62 µC, calculate the magnitude and direction of the force on it.

A 8-g charged plastic sphere charged to 75 µC is on top of a plastic spring with spring constant k = 400 N/m, which has a relaxed length of 10 cm. You then place another charged object 1 cm above (not touching) the sphere. Now, the spring is 9.5 cm long. Find the charge on the new second object.

An infinite line of positive charge lies along the y axis, with charge density A = 1.10 µC/m. A dipole is placed with its center along the x axis at x = 21.0 cm. The dipole consists of two charges ±10.0 µuC separated by 2.00 cm. The axis of the dipole makes an angle of 25.0° with the x axis, and the positive charge is farther from the line of charge than the negative charge. Find the net force exerted on the dipole.

Three charges are arranged along the x-axis. Two of the charges locations are known. Q1 = 4 nC and is located at the origin. Q2 = -8 nC is located 6 cm to the left of the origin. The third charge, Q3 is in equilibrium. (a) What is the location of Q3? (b) Does the charge of Q3 matter when determining its location? Explain.

Two charged spheres on a frictionless horizontal surface are attached to opposite ends of a string & are in static equilibrium. The 39 kg red sphere has more charge than the 22 kg green sphere. The total charge magnitude on the spheres is 120 ?C & they have the same polarity. As a result the tension is 202.5 N & the centers of the spheres are 0.39 m apart. Find the charge magnitude on each sphere. Qred (bigger charge) = Qgreen (smaller charge) =