Module Quiz Covers all 12 lessons

Module 14 Quiz: Further Work with Vectors

Comprehensive assessment covering vectors in three dimensions, vector operations and magnitude, the scalar (dot) product and the angle between vectors, projections, the vector, parametric and Cartesian equations of a line, intersecting and skew lines, and vector proof.

Multiple Choice

Q11 MARK

The magnitude of $\mathbf{a} = 2\mathbf{i} - 3\mathbf{j} + 6\mathbf{k}$ is:

Q21 MARK

If $\mathbf{a} = (1, 2, 3)$ and $\mathbf{b} = (4, -1, 2)$, then $\mathbf{a} + \mathbf{b}$ equals:

Q31 MARK

For $\mathbf{a} = (1, 2, 3)$ and $\mathbf{b} = (4, -1, 2)$, the dot product $\mathbf{a} \cdot \mathbf{b}$ is:

Q41 MARK

Two non-zero vectors are perpendicular if and only if their dot product equals:

Q51 MARK

The angle $\theta$ between two non-zero vectors $\mathbf{a}$ and $\mathbf{b}$ satisfies:

Q61 MARK

Which pair of vectors is perpendicular?

Q71 MARK

A unit vector in the direction of $\mathbf{a} = (2, -1, 2)$ is:

Q81 MARK

The vector equation of the line through the point with position vector $\mathbf{a}$, parallel to $\mathbf{d}$, is:

Q91 MARK

On the line $\mathbf{r} = (1, 0, 2) + \lambda(2, 1, -1)$, the point corresponding to $\lambda = 2$ is:

Q101 MARK

Two lines in three dimensions that do not intersect and are not parallel are said to be:

Q111 MARK

The scalar projection of $\mathbf{a}$ onto $\mathbf{b}$ is:

Q121 MARK

If $\mathbf{a} \cdot \mathbf{b} = 0$ and neither vector is the zero vector, then the angle between them is:

Q131 MARK

The vectors $(2, 4, 6)$ and $(1, 2, 3)$ are:

Q141 MARK

For any vector $\mathbf{a}$, the dot product $\mathbf{a} \cdot \mathbf{a}$ equals:

Q151 MARK

The lines $\mathbf{r} = (0, 0, 0) + \lambda(1, 1, 1)$ and $\mathbf{r} = (1, 0, 0) + \mu(1, 1, 1)$ are:

Short Answer

1. Find the magnitude of $\mathbf{a} = 4\mathbf{i} - 3\mathbf{k}$. (1 mark)

2. Given $\mathbf{a} = (2, 1, -2)$ and $\mathbf{b} = (1, 3, 0)$, find $\mathbf{a} \cdot \mathbf{b}$. (1 mark)

3. Find the angle between $\mathbf{a} = (1, 0, 0)$ and $\mathbf{b} = (1, 1, 0)$, in degrees. (2 marks)

4. Find a unit vector in the direction of $\mathbf{v} = (3, -4, 0)$. (2 marks)

5. Determine whether $\mathbf{a} = (1, 2, -1)$ and $\mathbf{b} = (3, -1, 1)$ are perpendicular, justifying your answer. (2 marks)

6. Write the vector equation of the line through $A(1, 2, 3)$ parallel to $\mathbf{d} = (2, -1, 4)$. (2 marks)

7. Find the scalar projection of $\mathbf{a} = (3, 4, 0)$ onto $\mathbf{b} = (1, 0, 0)$. (2 marks)

8. Show that the points $A(1, 1, 1)$, $B(2, 3, 5)$ and $C(3, 5, 9)$ are collinear. (2 marks)

9. Find the value of $t$ for which $(t, 2, 3)$ and $(4, -2, 1)$ are perpendicular. (2 marks)

10. Find the point of intersection of the lines $\mathbf{r} = (1, 0, 0) + \lambda(1, 1, 0)$ and $\mathbf{r} = (0, 1, 0) + \mu(1, -1, 0)$. (3 marks)