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Work Done When Force Is Varying

the work done...

Question

the work done by force is defined as a dot product of force vector and displacement vector of the point of application of force.if the point of application of force F=5i-3j+2k is moved from r1=2i+7j+4k to r2=-5i+2j+3k the work done by force is

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Solution

Force, F = 5i - 3j + 2k
Displacement = r₂ – r₁ = (-5i + 2j + 3k) – (2i + 7j + 4k) = -7i -5j – k
Work = (5i - 3j + 2k) . (-7i -5j – k) = -35 + 15 – 2 = -22 units

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Work Done When Force Is Varying

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