Mechanical Vibr...

A mass-spring-dashpot system (W = 365 N) is subjected to a sinusoidal force. What will be the total spring force at resonance if the force is F₀ = 40 N and the damping ratio is 0.05?

A shaft with natural frequency 50 rad/sec is rotated at frequency 25 rad/sec. What is transverse deflection produced (mm) if eccentricity of centre of mass is 9 mm?

A shaft has 2 rotors mounted on. The transverse natural frequencies, considering each of rotor separately, are 100 cycles/sec and 200 cycles/sec respectively. The lower critical speed is____

A 40000 gram rotor has an eccentricity 0.012 m. It is mounted on a shaft and bearing system whose stiffness is 320 kN/m and has a dumping factor of 0.07. What is the amplitude of whirling when the rotor operates at (100/6) rev/sec ?

A spring damper mechanical system supports a rotor of mass 1200 kg having an unbalance of 1.5 kg at 6 cm radius. The rotor is running at 1200 rpm and the damping ratio is found to be 0.30. Then the amplitude of vibration if the resonance occurs at 1550 rpm is ___________mm

A mass of 200 kg is suspended on a spring having a of 35 kN/m and is acted upon by a harmonic force of 100 N at undamped natural frequency. The damping may be considered to be viscous with a coefficient of 200 N.s/m. The value of damped natural frequency and amplitude of vibration of the mass will be

A spring mass damper system is subjected to an external force F­₀cosωt. The amplitude of vibration is 14 mm under damped resonance condition. When the frequency is reduced to 75 % of natural frequency the amplitude reduces to 10 mm, the damping ratio of this system is ____

An engine is mounted on a rubber pads such that the deflection is 5 mm. If the engine and coupling weigh 400 kg above, what speed (in rpm) must the motor run for 90% isolation?

A power transmission shaft has diameter of 30 mm and 900 mm long, and simply supported. The shaft carries a rotor of 4 kg at its mid-span. The rotor has an eccentricity of 0.5 mm. What is the critical speed of shaft in rpm?

Neglect mass of shaft take E = 2 × 10⁵ MPa.