Dynamics of Machinery
102602Module 6: Mechanical Vibrations
1(i). In viscous damping, the damping force is proportional to: (i) Displacement (ii) Velocity (iii) Acceleration (iv) Mass.20262m
Module 6: Mechanical Vibrations
View this question on its own page →In viscous damping, the damping force is proportional to: (i) Displacement (ii) Velocity (iii) Acceleration (iv) Mass.
1(j). The ratio of actual damping coefficient to critical damping coefficient is called: (i) Frequency ratio (ii) Damping ratio (iii) Transmissibility ratio (iv) Amplitude ratio.20262m
Module 6: Mechanical Vibrations
View this question on its own page →The ratio of actual damping coefficient to critical damping coefficient is called: (i) Frequency ratio (ii) Damping ratio (iii) Transmissibility ratio (iv) Amplitude ratio.
7(a). A single-degree damped vibrating system has mass 7.5 kg and makes 24 free oscillations in 14 seconds. The amplitude reduces to 0.25 of its initial value after five oscillations. Determine (i) spring stiffness, (ii) logarithmic decrement, and (iii) damping factor (system damping/critical damping).20267m
Module 6: Mechanical Vibrations
View this question on its own page →A single-degree damped vibrating system has mass 7.5 kg and makes 24 free oscillations in 14 seconds. The amplitude reduces to 0.25 of its initial value after five oscillations. Determine (i) spring stiffness, (ii) logarithmic decrement, and (iii) damping factor (system damping/critical damping).
7(b). A mechanical vibrating system has mass 8 kg and equivalent spring stiffness 5.4 N/mm. A dashpot exerts a force of 40 N when the mass velocity is 1 m/s. Find (i) critical damping coefficient, (ii) damping factor, (iii) logarithmic decrement, and (iv) ratio of two consecutive amplitudes.20267m
Module 6: Mechanical Vibrations
View this question on its own page →A mechanical vibrating system has mass 8 kg and equivalent spring stiffness 5.4 N/mm. A dashpot exerts a force of 40 N when the mass velocity is 1 m/s. Find (i) critical damping coefficient, (ii) damping factor, (iii) logarithmic decrement, and (iv) ratio of two consecutive amplitudes.
8(a). Explain the principle of vibration isolation and transmissibility in mechanical vibration systems. Derive the expression for the transmissibility ratio.20267m
Module 6: Mechanical Vibrations
View this question on its own page →Explain the principle of vibration isolation and transmissibility in mechanical vibration systems. Derive the expression for the transmissibility ratio.
9(d). Write a short note on underdamping, critical damping and overdamping.20267m
Module 6: Mechanical Vibrations
View this question on its own page →Write a short note on underdamping, critical damping and overdamping.