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# Lesson Worksheet: Moment of a Force about a Point in 3D Mathematics

In this worksheet, we will practice finding the moment of vector forces acting on a body about a point in 3D.

**Q1: **

True or False: If the force acts at point , then its moment in 3D space about point is given by .

- AFalse
- BTrue

**Q5: **

Find the moment of the force about the origin point, given that , and is acting at a point whose position vector is with respect to the origin point, then determine the length of the perpendicular segment drawn from the origin point to the line of action of the force .

- A, length units
- B, length units
- C, length units
- D, length units

**Q6: **

A force acts at point . Find the moment of this force about the point .

**Q8: **

The forces and act along and , respectively, as shown in the figure. Given that , , and are a right system of unit vectors in the directions of , , and , respectively, find the sum of the moments of the forces about point in newton-metres.

- A
- B
- C
- D