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Q5A) A motor rotating at 800 RPM and accelerate uniformly until it reaches the speed of 1800 RPM. During this period, it makes 565 complete revolutions. LO 2_1 Determine: a) The angular acceleration of the motor and the time taken from 800 RPM to 1800 RPM. b) The number of revolutions from stationary to 18ooRPM, assuming the angular acceleration is same as part (a). 06A) An experimental solid disc flywheel has a mass of 120 kg and an outside diameter of 300 mm. When the flywheel is at rest, a constant torque of 10 Nm Lo 2_1′ 22 is applied for a period of 2 seconds. Assuming for flywheel the radius of gyration K = r NZ. Calculate: a) The moment of inertia and the angular acceleration b) The angular velocity, the angular Kinetic Energy and the power required. Q7A) A solid flywheel on a machine has a mass of 9ookg and 8oomm in diameter. The wheel is rotating at 15oRPM. For solid flywheel, the radius of gyration K r N2. Calculate: Lo 2.1, 2.2 a) Store of Kinetic Energy in the flywheel. b) Decrease in speed of flwvheel (in RPM) if 1.5 kJ of energy is transferred from the wheel to do work in a process carried out by the machine. Q8A) An object of mass 0.3 kg oscillates with S.H.M of frequency 25 Hz (mass spring system). Determine: Lo 2.3 a) The periodic time and restoring force acting on the object when it is at displacement of 5omm. b) The stiffness of the spring

Q98) A flywheel has 7omm inside and 8oomm outside diameters. The thickness of the wheel is 6omm, and it is made of steel with density of 78ookg/m3. The flywheel accelerates from stationary and reaches 15ooRPM after 280 complete revolutions by a uniform torque. There is an opposing torque of 3oNm due to friction (output load). Assuming the radius of gyration K = rm N2 (rm is the mean radius). Calculate: a) The moment of inertia of the flywheel and change in Kinetic Energy. b) The value of the driving torque. c) The power input and the power output. d) The efficiency of the flywheel. 0108) For the following symmetrical (l) section horizontal beam: a) Calculate the reaction forces. b) Draw shear force and bending moment diagrams and from the diagrams determine the maximum bending moment. 0) Calculate the second moment of area and the maximum bending stress. I Give your answer in MN/mz. d) Suggest a solid square section of the beam if the maximum bending moment and bending stress remain the same. What is the factor of safety if the maximum yield stress of the beam material is 4ooMN/m2?