The figure below shows a simple model of a motor vehicle that can vibrate in the vertical direction while traveling over a rough road. The vehicle has a mass of

1200kg. The suspension system has a spring constant of 400 kN/m and a damping ratio of 3=0.5. If the vehicle speed is20 km/hr, determine the displacement amplitude of the vehicle. The road surface varies sinusoidally with an amplitude of Y = 0.05m and a wavelength of 6m. a) Find determine the displacement amplitude of the vehicle (X) \text { b) Find } \phi