Cogito
Precalculus · Chapter 3 · Lesson 3
Vector Applications
Forces, headings, and the resultant.
12 problems · about 22 minutes · TEKS P.4.G, TEKS P.4.J
Figure — use these to answer the problems
- Vector a(3, 0)
- Vector b(0, 4)
- a + b(3, 4)
Warm Up
Straightforward practice. Get the method working first.
5 problemsForces (0, 5) and (12, 0) act together. Magnitude of the resultant?
AnswerWhy can magnitudes not simply be added?
- Direction matters, so components must be added instead.
- Because of rounding errors.
(5, 2) + (1, 6). What is the y component?
AnswerMagnitude of (6, 8)?
AnswerA vector of magnitude 10 at 0°. What is its x component?
Answer
Build It Up
The same ideas with more to keep track of.
3 problemsA vector of magnitude 10 at 90°. What is its x component?
AnswerA boat rows east at 12 and a current pushes north at 5. Resultant speed?
AnswerForces (4, 3) and (−4, −3). Magnitude of the resultant?
Answer
Stretch Yourself
Mixed problems. Work out what kind of question it is before you start.
4 problemsWhich quantities are vectors?
- Velocity
- Force
- Mass
- Temperature
- Tick every box that applies.
A plane flies north at 300 with a 40 westward wind. Resultant speed, to the nearest whole number?
AnswerThe Resultant
Forces (3, 0) N and (0, 4) N act together. What is the magnitude of the resultant, in newtons?
AnswerNThe Balance
Two forces are (6, −2) N and (−6, 2) N. What is the magnitude of the resultant, in newtons?
AnswerN