Q1) An elevator car has a mass of (1600 kg) and is carrying passengers having a combined mass of (200 kg). A constant friction force of (4000 N) retards its motion upward, as shown in figure. (A) What power delivered by the motor is required to lift the elevator car at a constant speed of 3 m/s? (B) What power must the motor deliver at the instant the speed of the elevator is v if the motor is designed to provide the elevator car with an upward acceleration of 1 m/s2? Motor

Q1) An elevator car has a mass of (1600 kg) and is carrying passengers having a combined mass of (200 kg). A constant friction force of (4000 N) retards its motion upward, as shown in figure. (A) What power delivered by the motor is required to lift the elevator car at a constant speed of 3 m/s? (B) What power must the motor deliver at the instant the speed of the elevator is v if the motor is designed to provide the elevator car with an upward acceleration of 1 m/s2? Motor

International Edition---engineering Mechanics: Statics, 4th Edition

4th Edition

ISBN:9781305501607

Author:Andrew Pytel And Jaan Kiusalaas

Publisher:Andrew Pytel And Jaan Kiusalaas

Chapter7: Dry Friction

Section: Chapter Questions

Problem 7.78P: The figure shows a steel bar being processed by a rolling mill. Given that P=80kN and r =0.016,...

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