Concepts and Vocabulary
True or False A vector is an object that has magnitude and direction.
Scalars are quantities that have only ______.
The product of a scalar \(a\) and a vector \(\mathbf{v}\) is called a(n) _____ ______ of \(\mathbf{v}\).
Multiple Choice The vectors \(-\mathbf{v}\) and \(\mathbf{v}\) have [(a) the same, (b) different] magnitude and the [(c) same, (d) opposite] direction.
Skill Building
State which of the following are scalars and which are vectors:
In Problems 6–14, use the vectors in the above figure to graph each of the following vectors:
\(2\mathbf{v}\)
\(-2\mathbf{v}\)
\(\mathbf{v} + \mathbf{w}\)
\(\mathbf{v}-\mathbf{w}\)
\(\mathbf{w}-\mathbf{v}\)
\(\mathbf{v}-2\mathbf{w}\)
\((\mathbf{v+w}) +3\mathbf{u}\)
\(\mathbf{v}+( \mathbf{w}+3\mathbf{u}) \)
\(2\,\mathbf{u}-\dfrac{1}{3}(\mathbf{v}-\mathbf{w})\)
In Problems 15–22, use the vectors in the figure below.
Find the vector \(\mathbf{x}\) if \(\mathbf{x}+\mathbf{B}=\mathbf{F}\).
Find the vector \(\mathbf{x}\) if \(\mathbf{x}+\mathbf{K}= \mathbf{C}\).
703
Write \(\mathbf{C}\) in terms of \(\mathbf{E}\) , \( \mathbf{D}\) , and \(\mathbf{F}\).
Write \(\mathbf{G}\) in terms of \(\mathbf{C}\) , \( \mathbf{D}\) , \(\mathbf{E}\), and \(\mathbf{K}\).
Write \(\mathbf{E}\) in terms of \(\mathbf{G}\) , \( \mathbf{H}\) , and \(\mathbf{D}\).
Write \(\mathbf{E}\) in terms of \(\mathbf{A}\) , \( \mathbf{B}\) , \(\mathbf{C}\) , and \(\mathbf{D}\).
What is \(\mathbf{A}+\mathbf{B}+\mathbf{K}+\mathbf{G}\)?
What is \(\mathbf{A}+\mathbf{B}+\mathbf{C}+\mathbf{H}+\mathbf{G}\)?
Applications and Extensions
Resultant Force Two forces \(\mathbf{F}_{1}\) and \( \mathbf{F}_{2}\) act on an object shown in the figure. Graph the vector representing the resultant force; that is, find \(\mathbf{F}_{1}+\mathbf{F}_{2}.\)
Resultant Force Two forces \(\mathbf{F}_{1}\) and \(\mathbf{F} _{2}\) act on an object shown in the figure. Graph the vector representing the resultant force; that is, find \(\mathbf{F}_{1}+\mathbf{F}_{2}.\)
Air Travel An airplane is flying due north at a constant airspeed of 560 \(\rm{mi/h}\). There is a wind \(75 \,\rm{mi/h}\) blowing from the east.
Air Travel An airplane maintains a constant airspeed of \(500 \,\rm{km/h}\) headed due west. There is a tail wind blowing at \(500 \,\rm{km/h}\).
Suppose \(\mathbf{v}\) and \(\mathbf{w}\) are nonzero vectors represented by arrows with the same initial point, and that the terminal points of \(\mathbf{v}\) and \(\mathbf{w}\) are \(P\) and \(Q\), respectively. Suppose the vector \(\mathbf{u}\) is represented by an arrow from the initial point of \(\mathbf{v}\) to the midpoint of the directed line segment \( \overrightarrow{\it PQ}\). Write \(\mathbf{u}\) in terms of \(\mathbf{v}\) and \( \mathbf{w}\).
Find nonzero scalars \(a\) and \(b\) so that \[ \begin{equation*} 4\mathbf{v}+a(\mathbf{v}-\mathbf{w})+b(\mathbf{v}+\mathbf{w})=\mathbf{0} \end{equation*} \]
for every pair of vectors \(\mathbf{v}\) and \(\mathbf{w}\).