The van de graaff electrostatic generator develops a charge of approximately −1×10−5c and a pith ball has charge of approximately 1 × 10−9c. which of the following describes the relationship between the size of the force the van de graaff exerts on the pith ball and the size of the force the pith ball exerts on the van de graaff ?
(a) the van de graaff exerts a much larger force on the pith ball.
(b) the pith ball exerts a much larger force on the van de graaff.
(c) the forces have the same magnitude.

In a unit cell of fcc structure, indicate the position of one of the tetrahedral interstitial sites by plotting the corresponding tetrahedron. do the same for one of the octahedral interstitial sites (in a separate fcc unit cell). mark the positions of all the tetrahedral and octahedral interstitial sites in the unit cells. how many equivalent tetrahedral sites and how many equivalent octahedral sites are contained in a fcc unit cell, respectively. what is the coordination number for a tetrahedral site and what is the coordination number for an octahedral site?