15 Suppose the automobile described in 14 now have a damping

1.5 Suppose the automobile described in 1.4 now have a damping coefficient c = 4700 N/m-s and it has a harmonic excitation. If the amplitude is 9 cm with both the cases of 1200 kb and 1500 kg mass. Calculate the change in damping ratio, maximum potential energy and energy dissipation if the maximum deflection still remains 9 cm.

See attached picture for 1.4

1.4 Find the natural frequency of the following system, where gears 1 (with pitch radius ri) and 2 (with pitch radius r2) together have moment of inertia Ji, gear 3 (with pitch radius r3) has moment of inertia Jz A massless spring k is installed as shown in figure 1.4p and the connection has mass m. Assume the system has a small rotation angle. ri r2 10.5r3 13 Figure 1.4p

Solution

damping ratio = 0.65

potentialenergy = mgh =2700*9 *10

=216 J