An electric dipole p is suspended as a torsion pendulum, which is allowed to pivot about the nz-axis only. The dipole has moment of inertia I and the torsion spring has Hooke constant K. In the absence of an electric Field the torsion pendulum's equilibrium orientation theta-not is equal to zero. The dipole's orientation is allowed to change only in the direction permitted by the torsion pendulum (i.e., rotation about the nz axis). A uniform electric Field E is applied. (a) Derive the equations of motion for the torsion pendulum for arbitrary dipole moment p and uniform electric Field E. (b) Find, from the equations of motion, the equilibrium orientation of the pendulum Theta-not(E) when the uniform electric field is E I'm not really even sure where to start with this problem. I know the equations: torque = p x E (for a dipole) torque = K*theta (for a torsion pendulum) torque = I*alpha (for rotation) Other than that, though, I don't know where to go. Am I supposed to solve for theta and derive the rest of the equations from there, or should I solve for alpha and integrate? Or am I on the wrong track completely? Any help would be much appreciated.