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A particle moves through an xyz coordinate system while a force acts on it. When the particle has the position vector r with arrow = (2.00 m)i hat − (3.00 m)j + (2.00 m)k, the force is F with arrow = Fxi hat + (7.00 N)j − (5.00 N)k and the corresponding torque about the origin is vector tau = (1.00 N · m)i hat + (0.400 N · m)j + (−0.400 N · m)k. Determine Fx. -I know that you have to find the vector components of F x r, and I did for j and k since i cancels out. But I keep getting the wrong answer. Please provide the solution and the correct answer. I only have three attempts left.

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Answer:

The question is incomplete, below is the complete question "A particle moves through an xyz coordinate system while a force acts on it. When the particle has the position vector r with arrow = (2.00 m)i hat − (3.00 m)j + (2.00 m)k, the force is F with arrow = Fxi hat + (7.00 N)j − (5.00 N)k and the corresponding torque about the origin is vector tau = (4 N · m)i hat + (10 N · m)j + (11N · m)k.

Determine Fx."

[tex]F_{x}=-1N.m[/tex]

Explanation:

We asked to determine the "x" component of the applied force. To do this, we need to write out the expression for the torque in the in vector representation.

torque=cross product of force and position . mathematically this can be express as

[tex]T=r*F[/tex]

Where

[tex]F=F_{x}i+(7N)j-(5N)k[/tex]  and the position vector

[tex]r=(2m)i-(3m)j+(2m)k[/tex]

using the determinant method to expand the cross product in order to determine the torque we have

[tex]\left[\begin{array}{ccc}i&j&k\\2&-3&2\\ F_{x} &7&-5\end{array}\right]\\\\[/tex]

by expanding we arrive at

[tex]T=(18-14)i-(-12-2F_{x})j+(12+3F_{x})k\\T=4i-(-12-2F_{x})j+(12+3F_{x})k\\\\[/tex]

since we have determine the vector value of the toque, we now compare with the torque value given in the question

[tex](4Nm)i+(10Nm)j+(11Nm)k=4i-(-12-2F_{x})j+(12+3F_{x})k\\[/tex]

if we directly compare the j coordinate we have

[tex]10=-(-12-2F_{x})\\10=12+2F_{x}\\ 10-12=2F_{x}\\ F_{x}=-1N.m[/tex]