Which to use->Dot or cross product

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To calculate the work done by the wind on the crate, the dot product should be used, as work is defined as the scalar product of force and displacement vectors. The displacement vector is d = (-3.0 m)i, and the force vector is F = (2.0 N)i + (-6.0 N)j. Using the dot product, W = F · d, results in W = (2.0 N)(-3.0 m) + (0)(-6.0 N) = -6.0 J. The negative value indicates that the work done by the wind is in the opposite direction of the displacement. Understanding the correct application of vector multiplication is crucial in physics problems.
Celestiela
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a crate is sliding (disregard friction) with d=(-3.0 m)i while a steady wind pushes against the crate F=(2.0 N)i + (-6.0 N)j

How much work is done by the wind on the crate?

Ok W=Fd so I want to multiply the two vectors together.

[(-3.0 N)i ]*[(2.0 N)i + (-6.0 N)j ]

Do I use a cross product or a dot product? Why?
 
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The answer is in the proper defining equation of work.
 
D'OH

Working on homework on the weekends again...

:zzz:

Thanks!
 
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