Calculating magnitudes of vectors

Click For Summary
SUMMARY

The discussion focuses on calculating the magnitudes of two vectors A and B given the equation A + B - 225j = 0. The participants utilized trigonometric equations to express the components of the vectors, specifically A = [Bcos(56)]/cos(42) for the x-component and A + Bsin(56) - 225 = 0 for the y-component. The final calculated values for the magnitudes are A = 127.05 and B = 168.85, confirming the correctness of the setup while noting a minor error regarding the notation of 'j' in the equations.

PREREQUISITES
  • Understanding of vector components and their calculations
  • Knowledge of trigonometric functions, specifically sine and cosine
  • Familiarity with algebraic substitution methods
  • Basic grasp of complex numbers and notation
NEXT STEPS
  • Study vector addition and subtraction in physics
  • Learn about trigonometric identities and their applications in vector calculations
  • Explore complex number representations and their relevance in vector analysis
  • Practice solving systems of equations using substitution and elimination methods
USEFUL FOR

Students studying physics or mathematics, educators teaching vector analysis, and anyone involved in engineering or applied sciences requiring vector calculations.

PAstudent
Messages
47
Reaction score
0

Vector picture.png

1. Homework Statement

Given the two vectors in the diagram, calculate their magnitudes if A+B-225j=0

Homework Equations


sum of x component= Acos(42)--Bcos(56)
sum of y component= Asin(42)+Bsin(56)--225j

The Attempt at a Solution


Find A and B use substitution

A= [Bcos(56)]/cos(42) from x comp.

plug that into y comp. to solve for B

[Bcos(56)sin(42)]/cos(42) + Bsin(56) -- 225j=0

After solving, I got B= 168.85 and A=127.05. Does that seem correct?
 
Physics news on Phys.org
I haven't checked your arithmetic, but your setup of the equations looks correct...except for those j's in the y component equations.

Chet
 

Similar threads

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