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Suppose you pull a nail at a constant rate using a mall puller as shown in Figure 9.23. Is the nail puller in equilibrium? What if you pull the nail with some acceleration -is the nail puller in then? In which case is the force applied to the nail puller larger and why?
Figure 9.23 A nail puller is a lever with a large mechanical advantage. The external forces on the nail puller are represented by solid arrows. The force that the nail puller applies to the nail (Fo) is not a force on the nail puller. The reaction force the nail exerts back on the puller (Fn) is an external force and is equal and opposite to Fo. The perpendicular lever arms of the input and output forces are li and l0
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