Lifting books - Potential Energy

AI Thread Summary
To calculate the minimum work required to stack six books, each weighing 30N and 4cm thick, the total height of the stack must be considered. The work done against gravity is determined by the formula W = F × d, where F is the force (weight of the books) and d is the distance moved. The distance for each book varies, with the bottom book requiring no lift and the top book needing to be lifted the full height of the stack. The total work can be calculated by summing the individual work done for each book as they are lifted to their respective heights. Understanding these principles is essential for solving the problem effectively.
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I need help on this proble:

A student has six books, all of them with a 4cm thickness and a weight of 30N. ¿What would be the minimum work to put the books in one pile, if the six books are in a table?
 
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