Engineering Mechanics - PKRB: Work and Energy
- PKRB: Work and Energy - General Questions
A man having a weight of 180 lb sits in a chair of the Ferris wheel, which has a weight of 15,000 lb and a radius of gyration of ko = 37 ft. If a torque of M = 80(103) lb • ft is applied about O, determine the angular velocity of the wheel after it has rotated 180°. Neglect the weight of the chairs and note that the man remains in an upright position as the wheel rotates. The wheel starts from rest in the position shown.
= 0.888 rad/s = 0.836 rad/s = 0.874 rad/s = 0.849 rad/s
The uniform slender rod has a mass of 5 kg. Determine the magnitude of the reaction at the pin O when the cord at A is cut and 
= 90°
The spool of cable, originally at rest, has a mass of 200 kg and a radius of gyration of kG = 325 mm. If the spool rests on two small rollers A and B and a constant horizontal force of P = 400 N is applied to the end of the cable, compute the angular velocity of the spool when 8 m of cable has been unraveled. Neglect friction and the mass of the rollers and unraveled cable.
= 10.00 rad/s = 12.31 rad/s = 17.41 rad/s = 40.0 rad/s
A chain that has a negligible mass is draped over a sprocket which has a mass of 2 kg and a radius of gyration of kO = 50 mm. If the 4-kg block A is released from rest in the position shown, s = 1 m, determine the angular velocity which the chain imparts th the sprocket when s = 2 m.
= 44.3 rad/s = 39.6 rad/s = 41.8 rad/s = 59.1 rad/s
The beam having a weight of 150 lb is supported by two cables. If the cable at end B is cut so that the beam is released from rest when = 30°, determine the speed at which end A strikes the wall. Neglect friction at B. Consider the beam to be a thin rod.