You have a vertical polyethylene rod. It is 30 cm. It Carries a negative charge Q=-3μC which is distributed uniformly allong it's length. A 51 gram marble of glass Carriies a positive q= +0.44 μC charge  . The marble hangs from the rod from a plastic string, 10 cm below the rod. What is the tension in the string?.  a. 0.8N b. 0.5N c.0.3N d. 0.2N e. 0N

Two small metallic spheres, each of mass m = 0.30 g, are suspended as pendulums by light strings from a common point as shown in the figure below. The spheres are given the same electric charge, and it is found that they come to equilibrium when each string is at an angle of 0 = 8.2° with the vertical. If each string has length L = 40.0 cm, what is the magnitude of the charge on each sphere? L m nC

A positive charge q, = 3.00 µC on a frictionless horizontal surface is attached to a spring of force constant k as in the figure shown below. When a charge of q, = -8.950 µC is placed 9.50 cm away from the positive charge, the spring stretches by 5.00 mm, reducing the distance between charges to d = 9.00 cm. Find the value of k. ww 92 N/m Need Help? Read It

Three charges are placed on a horizontal line. Charges q1 = +7 nC and q2 = -3 nC are fixed in place, with q2 2.0 m to the right of q1. Charge q3=+5 nC is in equilibrium but free to slide on the line (but not off of it.) a. Find the distance between q3 and q1 and whether q3 is to the right or left of q1. b. If q3 can move along the line away from its initial location, is the equilibrium stable or unstable? How did you decide? c. If q3 were were on a vertical line instead, so it could move up and down but not horizontally, would the equilibrium be stable or unstable for that motion? How did you decide? m

A particle (charge = +40 μC) is located on the x axis at the point x = -20 cm, and a second particle (charge = +50 μC) is placed on the x axis at x = +30 cm. What is the magnitude of the total electrostatic force on a third particle (charge = - 4 μC) placed at the origin (x = 0)?   a. 56 N b. 16 N c. 35 N d. 41 N e. 72 N

Q4.Three point charges lie along the x axis as shown in the picture on the right side. The positive charge q,=15.0µC is at x= 2.00m, the positive charge q, =6.00µC is at the ori- gin(0,0), and the net force acting on q, is zero. What is the x coordinate of q,? 2.00 m Ex +– 2.00 – x - 12 F23 43 F13

A 0.10 g honeybee acquires a charge of 20 pC while flying. The electric field near the surface of the earth is typically 100 N/C , directed downward. What is the ratio of the electric force on the bee to the bee's weight? What electric field strength would allow the bee to hang suspended in the air?

A hollow conducting sphere has an inside radius of r1 = 0.17 m and an exterior radius of r2 = 0.27 m. The sphere has a net charge of Q = 5.4E-06 C.   What is the field E1 in N/C 1 m from the sphere's exterior surface? What is the magnitude of the field at a distance of 0.05 m from the center of the sphere?

In the figure four particles form a square with edge length a = 3.02 × 10-2 m. The charges are q₁ = 94 = 2.37 × 10-15 ℃ and 92 = 93 = q. (a) What is q if the net electrostatic force on particle 1 is zero? (b) Is there any value of q that makes the net electrostatic force on each of the four particles zero? a a

Two particles, one with charge -7.13 µC and one with charge 3.55 µC, are 6.59 cm apart. What is the magnitude of the force that one particle exerts on the other? force: TOOLS 93=== Two ne x10 entical positive charge qs, are placed the same 6.59 cm apart, and the force between them is measured to be the same as that between the original particles. What is q? N HC