(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Find the magnitude of the vector product w ⃗x u, where w=<1,0,1> and u=<1,1,0>.

2. Relevant equations

||w x u|| = ||w|| ||u|| sin θ

cos θ = [itex]\frac{w.u}{||w|| ||u||}[/itex]

3. The attempt at a solution

w ⃗x u ⃗= -i ̂+j ̂+k ̂

‖||w ⃗x u|| ⃗ ‖= √3

but

cosθ= (w ⃗∙ u ⃗)/(‖||w|| ⃗||u||) ⃗ ‖ = 1/(√2 √2) implying ⟹ θ=[itex]\pi[/itex]/4

which then makes

‖||w ⃗x u|| ⃗ ‖= ‖||w|| ⃗||‖‖u|| ⃗sinθ

become

‖||w ⃗x u|| ⃗ ‖= √2 √2 sin〖[itex]\pi[/itex]/4

or the sqrt(2).

What's wrong here?

1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

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# Homework Help: Magnitude of Cross Product Mismatch

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