A spherical conductor with a 0.193 m radius is initially uncharged. How many electrons should be removed from the sphere in order for it to have an electrical potential of 7.10 kV at the surface?

The number of electrons removed is  

Explanation:

From hr question we are told that

    The radius is  

   The required electrical potential is

The total charge on the sphere  is mathematically evaluated as

where k is the coulombs constant with value

substituting value

The number of electron removed is mathematically evaluated as

Where e is  the charge on one electron with value

  substituting values  

two charges are fixed in place on the x-axis as shown. the charge at x = 0 is negative and has magnitude q = 2 μcoulombs (1 μcoulomb = 10-6 coulombs). the charge at x = d, (d = +12 cm), is positive and has magnitude q = 4 μcoulombs. find a point x = xo along the x-axis at which the electric field is zero.