Can someone explain this to me

  • Thread starter Thread starter xpack
  • Start date Start date
  • Tags Tags
    Explain
Click For Summary
SUMMARY

The discussion centers on calculating speed and bearing using trigonometric principles. The speed, denoted as s, is derived from the equation s^2 = 4^2 + 9^2, resulting in s = 19.4 mph. The angle Ө is calculated using Tan^(-1) [19/4], yielding 78.1°. The correct three-figure bearing is 101.9°, which translates to N 11.9° W, clarifying a common misunderstanding regarding the bearing notation.

PREREQUISITES
  • Understanding of basic trigonometry, specifically tangent functions.
  • Familiarity with speed and distance calculations.
  • Knowledge of navigation and bearing notation.
  • Ability to perform square root calculations.
NEXT STEPS
  • Study the application of the Pythagorean theorem in real-world scenarios.
  • Learn about advanced trigonometric functions and their applications in navigation.
  • Explore the concept of bearings and how to convert between different formats.
  • Investigate the use of speed and distance in physics problems.
USEFUL FOR

Students in mathematics or physics, navigators, and anyone interested in understanding speed and bearing calculations in practical applications.

xpack
Messages
37
Reaction score
0
Let speed be s

s^2 = 4^2 + 9^2

s^2 = 377

s = 19.4 mph

Ө = Tan^(-1) [ 19/4 ] = 78.1°

3 figure bearing is thus 180 ° - 78.1 ° = 101.9 °

109.1 ° = N 11.9 ° W

Why 109.1 ° = N 11.9 ° W.
 
Physics news on Phys.org
You have a typo at the end of your post.

xpack said:
Let speed be s

s^2 = 4^2 + 9^2

s^2 = 377

s = 19.4 mph

Ө = Tan^(-1) [ 19/4 ] = 78.1°

3 figure bearing is thus 180 ° - 78.1 ° = 101.9 °

109.1 ° = N 11.9 ° W.

Why 109.1 ° = N 11.9 ° W.

It isn't: the result is [tex]101.9^\circ[/tex], not [tex]109.1^\circ[/tex]. With N at [tex]90^\circ[/tex], the result is [tex]11.9^\circ[/tex] west of that, hence the [tex]N 11.9^\circ W[/tex].
 
Oh man! So stupid of me. Thanks!
 

Similar threads

Replies
7
Views
4K
  • · Replies 2 ·
Replies
2
Views
2K
Replies
1
Views
2K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 14 ·
Replies
14
Views
3K
  • · Replies 2 ·
Replies
2
Views
1K
Replies
4
Views
3K
  • · Replies 21 ·
Replies
21
Views
2K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 25 ·
Replies
25
Views
5K