(a) State Kennedy’s Theorem for instant centres and show how it is used to find the centres. Illustrate your answer using sketches of a 4-bar linkage and show how the method be used to find velocity and acceleration at any point in a linkage. [5] (b) In the four-bar linkage mechanism shown in Figure Q5b link AD is fixed and is 15 cm long. The crank AB is 5 cm long and rotates at 120 rpm clockwise while link CD which rotates about Dis 8 cm long. The connecting link BC is 11 cm in length. The angle, <BAD, is 60°. (i) Find the angular velocity of link CD. [10] For the mechanism shown in Figure Q5b the torque being input at the crank AB is 10 Nm. What is the torque being delivered at the output link CD.