What is the work done when a 10kg box is being pushed by a 50kg boy to a distance of 10m? A laborer pulled a bucket of cement weighing 500 N from the ground to the first floor of a building using a pulley system. The first floor is 10 m from the ground. What is the work done by the laborer?

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Answer i believe its center of gravity

From a chemical point of view, proteins are by far the most structurally  complex  and functionally sophisticated molecules known. this is perhaps not surprising, once one realizes that the structure and chemistry of each  proteinhas been developed and fine-tuned over billions of years of evolutionary history. we start this chapter by considering how the location of each  amino acid  in the long string of amino acids that forms a protein determines its three-dimensional shape. we will then use this understanding of protein structure at the atomic level to describe how the precise shape of each protein  molecule  determines its function in a cell.

In the absence of air resistance, there is no force acting horizontally therefore after one second, the forward velocity will remain 40m/s

the downward acceleration is 9.8m/s2. therefore after one second the downward velocity after one second will be 9.8 m/s