For the followingproblem choose the best answer and EXPLAIN why you chose theanswer. Two identical conducting spheres are charged to +2Q and -Q, respectively, and are separated by a distance d (much greater than the radii of the spheres). The magnitude of the force of attraction on the left sphere is F1. After the two spheres are made to touch and then are reseparated by distance d, the magnitude of the force on the left sphere is F2. Which of the following relationships is correct? 2F1 = F2 F1 = F2 F1 = 2F2 F1 = 4F2 F1 = 8F2
Explanation / Answer
the electric force initially F=2k*Q2/d2 after the charges are resdistributed equally for 2sphere=(2Q-Q)/2=Q/2 => F'=1/8*2k*Q2/d2=1/8*F =>answer D after the charges are resdistributed equally for 2sphere=(2Q-Q)/2=Q/2 => F'=1/8*2k*Q2/d2=1/8*F =>answer D