• # question_answer A slender shaft supported on two hearings at its ends carries a disc with an eccentricity e from the axis of rotation. The critical speed of the shaft is N. If the disc is replaced by a second one of the same weight but mounted with an eccentricity 2e, critical speed of :he shaft in the second case is: A) $\frac{1}{2}N$                        B) $\frac{1}{\sqrt{2}}N$C) N                                 D) 2N

${{\omega }_{n}}={{\omega }_{c}}=\sqrt{\frac{k}{m}}$ Critical speed is not a function of eccentricity. Hence critical speed does not change.