A block is pulled along the ground by a constant force (in newtons) through a…

PHYSICS · Multi-part · A Level · Physics · Mechanics and materials · Mechanics and materials

Problem

A block is pulled along the ground by a constant force F⃗=3i+4j−2k\vec{F}=3\mathbf{i}+4\mathbf{j}-2\mathbf{k} (in newtons) through a displacement d⃗=5i−j+2k\vec{d}=5\mathbf{i}-\mathbf{j}+2\mathbf{k} (in metres). (i) Compute the work done by the force during this displacement. (ii) Identify and justify whether each of the following quantities is a vector or a scalar: force F⃗\vec{F}, displacement d⃗\vec{d} and work done WW. (iii) The block is next moved through a second displacement d ′⃗=−2i+4j\vec{d\,'}=-2\mathbf{i}+4\mathbf{j} m by a new force F ′⃗=6i−3j+k\vec{F\,'}=6\mathbf{i}-3\mathbf{j}+\mathbf{k} N. Without re-deriving formulas, determine the total work done in the two displacements and classify your final answer as vector or scalar with suitable reasoning.

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