Is the Electrostatic Force Calculation Correct for Inclined Bar and Wire?

Click For Summary
SUMMARY

The discussion focuses on calculating the electrostatic force between a charged bar with linear charge density λ2 and a straight wire with linear charge density λ1, where the bar is inclined at an angle α. The user correctly identifies the electric field generated by the wire as E = λ1 / (2πε0 x) and establishes the relationship dq2 = λ2 dl, with dl expressed in terms of dx and α. The integration limits for calculating the force F are set from H - (L/2)sinα to H + (L/2)sinα, which are appropriate for the geometry described. The user seeks confirmation on the correctness of their calculations and integration setup.

PREREQUISITES
  • Understanding of electrostatics and electric fields
  • Familiarity with linear charge density concepts
  • Knowledge of calculus, particularly integration techniques
  • Basic grasp of geometry related to inclined angles
NEXT STEPS
  • Review the derivation of electric fields from linear charge distributions
  • Study integration techniques for variable limits in calculus
  • Explore the implications of angle α on electrostatic force calculations
  • Investigate numerical methods for solving complex electrostatic problems
USEFUL FOR

Physics students, electrical engineers, and anyone involved in electrostatics or force calculations in charged systems.

hastings
Messages
80
Reaction score
0
find electrostatic force

problem:
there's a long straight wire with a λ1 charge. at some distance from it there's a bar charged with a λ2 charge. the bar is not parallel to the straight wire, instead it's inclined with an angle "alpha" between the dotted line, parallel to the wire, passing through the middle of the bar(point A), and the bar itself. The entire bar is long L. the distance between the wire and point A, is H.

Please check out the diagram.

What I did:

E=\frac{\lambda_1}{2\pi\epsilon_0 x} this is the electrical field generated by the wire.

dq_2=\lambda_2 dl . is this right? Then...

dx=dl \sin\alpha \longrightarrow dl=\frac{1}{\sin\alpha}dx . if this is right then I substitute in the above relation:

dq_2=\lambda_2 dl=\lambda_2\frac{1}{\sin\alpha}dx Is this correct till this point?

F=\int_{H- \frac{L}{2}\sin\alpha}^{H+\frac{L}{2}\sin\alpha} dF

Are the extremes of integration right?

Now the big problem is putting the pieces together.

F=\int_{H-\frac{L}{2}\sin\alpha}^{H+\frac{L}{2}\sin\alpha}dF= \int_{H-\frac{L}{2}\sin\alpha}^{H+\frac{L}{2}\sin\alpha}Edq_2=\int_{H-\frac{L}{2}\sin\alpha}^{H+\frac{L}{2}\sin\alpha}\frac{\lambda_1}{2\pi\epsilon_0 x}\lambda_2dl=\int_{H-\frac{L}{2}\sin\alpha}^{H+\frac{L}{2}\sin\alpha}\frac{\lambda_1}{2\pi\epsilon_0 x}(\lambda_2 \frac{1}{\sin\alpha }dx)


Could you tell me whether I need to fix anything?
 

Attachments

  • prob2.jpg
    prob2.jpg
    4.1 KB · Views: 490
  • prob2.1.jpg
    prob2.1.jpg
    10 KB · Views: 496
Last edited:
Physics news on Phys.org
Is it correct? Is it wrong?
 

Similar threads

  • · Replies 19 ·
Replies
19
Views
2K
Replies
9
Views
3K
Replies
12
Views
3K
Replies
4
Views
4K
Replies
4
Views
5K
  • · Replies 9 ·
Replies
9
Views
858
  • · Replies 5 ·
Replies
5
Views
1K
  • · Replies 2 ·
Replies
2
Views
2K
Replies
1
Views
3K
  • · Replies 2 ·
Replies
2
Views
2K