1. The problem statement, all variables and given/known data A water molecule is a permanent dipole with a dipole moment p = qs. There is a water molecule in the air a very short distance x from the midpoint of a long rod of length L and uniform charge +Q. The axis of the rod is perpendicular to the rod. Note that s << x << L. a) Find the the force of the rod on the molecule in terms of Q, L, x, p. b) If the electric field on the molecule when it is 1 cm from the rod is 10^6 N/C and p = 6*10^-30 and the mass of the molecule is m. What is the acceleration of the molecule? 2. Relevant equations F = ma For a rod: F = k(Q/r*sqrt(r^2 + (L/2)^2)), k = 9*10^9 F = qE 3. The attempt at a solution I have done a and get: Force of rod on molecule: F = 2kQp/Lx^2 (toward the rod and perpendicular to it) My problem is that I'm not sure how to get b. I don't know how to eliminate using given data, Q and L. Please help. Thank you.