Q1.
(d) A beam AB is simply supported over a span of 15 m. An u.d.l of 25 kN/m intensity and 5 m length moves over the beam from end A to B. Draw the influence line diagram for bending moment and shear force at section C located at 6 m from end A. Hence calculate the maximum bending moment and shear force at section C.
(e)
A motor of 150 kg mass is supported by four springs as shown in figure. Each of the springs has a stiffness of 120 kN/m. The unbalance of the rotor is equivalent to a mass of 40 g located at 150 mm from the axis of rotation. The motor is constrained to move vertically. Find
(i) the speed of motor at which resonance will occur
(ii) the amplitude of vibration of the motor when the speed is 1000 rev./m.