A mine elevator is supported by a 2.2 cm diameter steel cable (Ultimate Strength = 600 MN/m2). The mass of the elevator and its contents is 800 kg. The modulus of elasticity of the cable is 570x103 MN/m2.
A. If the elevator is accelerating down at 3.1m/s^2, by how much is the cable stretched when the elevator is 274m below earth’s surface.
B. If the elevator is stationary, by how much is the cable stretched when the elevator is 274m below earth’s surface.
C. If the elevator is accelerating up at 3.1m/s^2, by how much is the cable stretched when the elevator is 274m below earth’s surface.
D. For the three cases above (A-C), what is the minimum factor of safety?