What is the charge on pith ball and tension in the string

Question

Assignment:

Problems:

1. A relatively heavy pith ball in the figure has a mass of 1.3 g and has acquired 1 percent of the charge. on a thin, ebonite rod by contact. If the charge on the rod is concentrated at one end and the distance of the pith ball from that end is 0.1 meter, what is the charge on the pith ball and the tension in the string? Assume the thread makes an angle of θ = 30° with respect the vertical?

2. Consider two charges, q₁ = 5 X 10^-8 C at location (-2 cm, 0) and q₂ = -4 x10^-8 C at (1 cm, 4 cm). Determine the position where a third charge Q should be placed for it to feel zero net force.

3. An alpha particle is a helium nucleus and therefore consists of two protons and two neutrons. Such particle has an initial velocity of +1.60 x 10³ m / s xˆ and enters a region where the electric field is E^→ = -500.N /C xˆ.

a) How much time passes before the alpha particle comes to rest?

b) How far has the alpha particle traveled during this time?