Apendulum consists of a rod ab of length 2a and mass m, rotating about a horizontal axis through its one end b. let 6 denote the counterclockwise angle that the rod forms with the vertical line drawn down from point b. (17) (a) find the equation of rotation of the pendulum (b) what is the total mechanical energy of the pendulum, if the rod is initially held horizontal and then released? assume that the zero energy level of the gravita- tional energy goes through point b. (c) give all the initial conditions (specify the initial angle of rotation and angular velocity) which will ensure that the kinetic energy of the pendulum will always stay the same.