(Solved): urgent plsthanks (a) Below is a diagram of a helicopter with an unbalanced mass on one of the tai ...

(a) Below is a diagram of a helicopter with an unbalanced mass on one of the tail rotor blades. Tail rotor blades Tail section, El Figure 1: Helicopter with unbalanced tail rotor blade The helicopter has 4 tail rotor blades, with a total mass of 20 kg, which includes the drive system. One of the tail rotor blades of a helicopter has an unbalanced mass of m, = 0.5 kg at a distance of e = 0.65 m from the axis of rotation. The equivalent mass of the tail rotor is determined to be the mass of the rotor plus one-quarter (1/4) the unbalanced mass. The tail section (AB) has a length of 6 m, a mass of 240 kg, and is made of steel with a flexural stiffness (El) of 2.25 MN/m and a damping ratio of 2 percent. Let X be the displacement of the tail section and k is the stiffness of the tail section. Determine the: (1) Stiffness of the tail section (ii) Natural frequency of the system. (3 Marks) (3 Marks) (3 Marks) (HI) Displacement of the system at the natural frequency Displacement of the system at steady state (approximately 1000 rad/s) (iv) (3 Marks) (v) Sketch a diagram showing the Inertia dynamic amplifier (Einert) vs rotational speed (rad/s) of the system on a logarithmic plot for both the horizontal and vertical axes, labelling all key information. (5 Marks) (b) Answer the following: