H1. A wooden block of mass m is pushed over a floor in a straight line in the x direction with a constant velocity vo > 0. At time t = 0, when the block is at position x = 0, it is no longer pushed and the block experiences only a constant sliding friction force F in the negative x-direction until it comes to rest. (i) Write down the equation of motion of the block for t > 0. Calculate the time, tx, at which the block comes to a stop and also find the distance, d, travelled by the block from the time when the pushing is stopped to the time when it comes to rest. (ii) Calculate the work done by the friction force from x = 0 to x=d, and then show that it is equal to the change in the kinetic energy of the block.

H1. A wooden block of mass m is pushed over a floor in a straight line in the x direction with a constant velocity vo > 0. At time t = 0, when the block is at position x = 0, it is no longer pushed and the block experiences only a constant sliding friction force F in the negative x-direction until it comes to rest. (i) Write down the equation of motion of the block for t > 0. Calculate the time, tx, at which the block comes to a stop and also find the distance, d, travelled by the block from the time when the pushing is stopped to the time when it comes to rest. (ii) Calculate the work done by the friction force from x = 0 to x=d, and then show that it is equal to the change in the kinetic energy of the block.

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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