(a) Figure 4.1 shows a simple pulley system that is used to lift a weight m of 10 kg by application of a force F. Assuming gravitational acceleration g = 10 m/s², Calculate: (i) the force F required to accelerate m to 2 m/s² in an upwards direction. You may assume the wheel and rope are frictionless. (ii) the work done during the first 3 s assuming m was initially at rest. Your solution should show ALL working out to attract full marks. (b) Add another two wheels, that can be either fixed or movable, to the pulley system in order to minimise the required pull force. You should draw the new pully system and determine the new force.

(a) Figure 4.1 shows a simple pulley system that is used to lift a weight m of 10 kg by application of a force F. Assuming gravitational acceleration g = 10 m/s², Calculate: (i) the force F required to accelerate m to 2 m/s² in an upwards direction. You may assume the wheel and rope are frictionless. (ii) the work done during the first 3 s assuming m was initially at rest. Your solution should show ALL working out to attract full marks. (b) Add another two wheels, that can be either fixed or movable, to the pulley system in order to minimise the required pull force. You should draw the new pully system and determine the new force.

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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