A particle position is described by position vector r = 3i + 2j and the force vector i - 2j acts on the object.(adsbygoogle = window.adsbygoogle || []).push({});

1) Find the torque about an axis through the origin and perpendicular to the xy plane. Draw the two vectors to check your torque direction.

I used the right hand rule and found out that the torque will have a negative direction. Then I used cross product term by term.

My torque is -8 k NM.

2) Find the torque about an axis through the point x = 5m, y = 5m perpendicular to the xy plane. Draw the two vectors to check your torque direction. The force should produce a roation about (5,5) consistent with your answer.

How do I do this? The answer is 7 z Nm. Do I find the torque the same way as for part 1, and then somehow take the distance between them into consideration? How come the direction is now positive?

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# Homework Help: Finding torque (vector cross product)

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