A loading crane has a cable extending from point P to point Q, represented by the vector **PQ** = {2, โ3, 4}. A force vector **F** = {6, โ2, โ1} acts on the cable. (a) Calculate the scalar projection of **F** on **PQ**. Express your answer in the form \(\frac{a\sqrt{b}}{c}\) where \(a\), \(b\), and \(c\) are positive integers with \(b\) square-free. (2 marks) (b) Hence, determine the vector projection of **F** on **PQ**, expressing your answer in the form {\(p\), \(q\), \(r\)} where \(p\), \(q\), \(r\) are simple fractions. (3 marks)
Specialist Mathematics ยท Unit 3 ยท Vectors in two and three dimensions ยท Algebra of vectors in three dimensions
Use scalar and vector projections of vectors. scalar projection of ๐ on ๐: |๐| cos(๐) = ๐ โ ๐ฬ vector projection of ๐ on ๐: |๐| cos(๐) ๐ฬ = (๐ โ ๐ฬ)๐ฬ = (๐โ ๐ ๐โ ๐) ๐
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Calculate the scalar projection of vector OP onto vector OQ.
Two vectors are defined as ฮฑ = (2, 3) and ฮฒ = (4, 1). Use the scalar product formula to determine the scalar projection of ฮฑ onto ฮฒ.
A surveyor needs to find the perpendicular distance from point $P$ to a fence line passing through the origin. The fence direction is given by vector $\mathbf{b} = \begin{pmatrix} 4 \\ 3 \\ 0 \end{pmatrix}$, and the position of $P$ relative to the origin is $\mathbf{p} = \begin{pmatrix} 6 \\ 8 \\ 0 \end{pmatrix}$. The surveyor first calculates the scalar projection of $\mathbf{p}$ onto $\mathbf{b}$ to determine the position along the fence. Which of the following is the scalar projection of $\mathbf{p}$ on $\mathbf{b}$?
Two vectors \(\vec{p} = [2, 1, -1]\) and \(\vec{q} = [1, 0, 1]\) are drawn from the origin as shown. Calculate the scalar projection of \(\vec{p}\) onto \(\vec{q}\), giving your answer in the form \(\frac{a}{\sqrt{b}}\) where \(a\) and \(b\) are positive integers.
Find the scalar projection of \(\mathbf{u} = \begin{bmatrix} 2 \\ -1 \\ 3 \end{bmatrix}\) onto \(\mathbf{v} = \begin{bmatrix} 1 \\ 2 \\ 2 \end{bmatrix}\).
The points T(2, โ1, 3) and Q(โ4, 2, 1) are joined to the origin O. Calculate the scalar projection of vector TQ onto vector OT.
A force **F** = \(\begin{bmatrix} 6 \\ -3 \\ 2 \end{bmatrix}\) newtons acts on an object that moves along a straight line in the direction of vector **d** = \(\begin{bmatrix} 2 \\ 2 \\ 1 \end{bmatrix}\) metres. (a) Calculate the scalar projection of **F** onto **d**. (1 mark) (b) Hence calculate the vector projection of **F** onto **d**. (2 marks)