Consider a thin rod of mass 1.4 kg, length 2.7 m and uniform density. The rod is pivoted at one end on a frictionless horizontal pin. The rod is initially held in horizontal position but eventually allowed to swing down.What is its angular acceleration at the instant it makes an angle 68 ? with the horizontal? The acceleration due to gravity is 9.8 m/s 2 . Answer in units of rad/s 2