An automobile whose riding characteristics are to be investigated is placed on a platform which can be moved up and down with simple harmonic motion. For the purpose of making preliminary calculations it is assumed that the body of the automobile has one degree of freedom in the vertical direction and that it is supported by suspension springs having a total stiffness of 50 kNm?¹. The total damping force offered by the shock absorbers is linearly viscous and is 6 kNsm?¹. The body has a mass of 1t and the tyres are assumed to be rigid. If the platform vibrates with an amplitude of 25mm and with a frequency equal to that of the undamped free frequency of the body on the suspension springs, determine the amplitude of the motion of the body.
Added by Alfredo A.
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First, we need to find the undamped natural frequency of the body on the suspension springs. We can use the formula: ωn = √(k/m) where ωn is the natural frequency, k is the total stiffness of the suspension springs, and m is the mass of the body. Plugging in the Show more…
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