(adsbygoogle = window.adsbygoogle || []).push({}); 1. A force F = (2.80 N)i + (6.80 N)j + (7.05 N)k acts on a 2.00 kg mobile object that moves from an initial position of di = (3.05 m)i - (2.00 m)j + (5.00 m)k to a final position of df = -(5.00 m)i + (4.05 m)j + (7.00 m)k in 4.00 s.

2. Relevant equations

W = Fd

3. The attempt at a solution

I thought I could do the pythagorean theorem for the Force...

square root (2.8^2 + 6.8^2 + 7.05^2), that would give the magnitude of the force.

Then I did the same thing, the magnitude of df - magnitude of di.

Then, (magnitude F) * (magnitude df - magnitude di) = W

But that is incorrect. I am using Web assign online and the answer I get from the previous method does not work. Can anyone explain?

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# Homework Help: Work/Force question, can anyone explain?

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