Question

A car and its suspension system act as a block of mass m= on a vertical spring with k 1.2 x 10 N m, which is damped when moving in the vertical direction by a damping force Famp =-rý, where y is the 1200 kg sitting 4. (a) damping constant. If y is 90% of the critical value; what is the period of vertical oscillation of the car? () by what factor does the oscillation amplitude decrease within one period? ( How long does it takes for the amplitude to decrease by a factor of 1000? (50 marks) A harmonic oscillator with mass of 1 kg and a spring constant of 8.75 N m (b) is subject to a damping force Fmp =-y, with y=6 kg s. The system is in equilibrium (x = 0) at time t= (0)=-45 cm s. Determine the displacement x(t) and velocity (t) thereafter. O, when an impulse gives it a velocity of (50 marks)

Answer 1

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