Q9. With reference to crankshafts, explain EACH of the following:
A. The cause and effects of torsional vibration;
B. The term critical speed indicating why it can be a problem;
C. The term fatigue cracking and state, with reasons, TWO factors of crankshaft operation which have greatest influence on the likelihood of fatigue cracking
D. How a torsional vibration damper can reduce the effects of torsional vibration