A small charged sphere, mass = 3.5 times 10\" kg, is suspended at equilibrium in
ID: 3161653 • Letter: A
Question
A small charged sphere, mass = 3.5 times 10" kg, is suspended at equilibrium in a uniform electric field from a pivot point by a mass less, non-conducting string as shown below. The string makes an angle of 35.0 degree with respect to the vertical. What is the charge on the sphere? In the figure below, the magnitude of charge 3 is 48 mC. What are the signs of the charges? What are the magnitudes of charges 1, 2, & 4? Three charges are located on the vertices of an equilateral triangle with sides of length 36.0 cm as shown below. What is the net electrostatic force on charge q_3? For the collection of charges in Problem 3, what is the electric field at the origin?Explanation / Answer
here,
m = 3.5 * 10^-9 kg
theta = 35 degree
let the charge on sphere be q and the tension in the string be T
equating the forces vertically
T * cos(theta) = m * g
T * cos(35) = 3.5 * 10^-9 * 9.8
T = 4.19 * 10^-8 N
equating the forces horizontally
T * sin(theta) = q * E
4.19 * 10^-8 * sin(35) = q * (-1350)
q = - 1.78 * 10^-11 C
the charge on the sphere is - 1.78 * 10^-11 C