Interference from two radio antennae - simplistic and workings include

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Homework Help Overview

The discussion revolves around the interference patterns created by two radio antennae, specifically focusing on the formulas for minima and maxima in wave interference. Participants are examining the conditions under which these patterns occur and the corresponding angles.

Discussion Character

  • Conceptual clarification, Mathematical reasoning, Assumption checking

Approaches and Questions Raised

  • Participants are exploring the correct formulas for minima and maxima, questioning the validity of their calculations and the assumptions behind the formulas. There is a focus on the angles derived from the equations and the implications of using non-integer values for m in the minima formula.

Discussion Status

There is ongoing clarification regarding the formulas used for minima and maxima. Some participants have pointed out potential errors in the original poster's calculations, while others are confirming the general method but questioning specific applications of the formulas. The discussion reflects a mix of attempts to correct misunderstandings and validate the original poster's reasoning.

Contextual Notes

Participants are working with specific formulas from their notes, which may not align with standard interpretations. There is an acknowledgment of possible mistakes due to late-night concentration issues, indicating a need for careful review of the material.

elemis
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Is this correct ?

I have an issue for the minima formula when n=1 I get theta = 90 degrees.

This doesn't make any sense.

Is my method correct ?
 

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Your general method is correct, but your formula for the minima is incorrect. Check your notes or text.
 
TSny said:
Your general method is correct, but your formula for the minima is incorrect. Check your notes or text.

The formulas listed were in my notes.

Okay, for minima : 2λsinθ = mλ m=0.5,1.5,2.5,3.5...

This would give me the required non-integr half wavelengths for a minima, correct ?

EDIT : Hence m =0.5 would mean the first minima is at 30 degrees.

maxima : 2λsinθ = nλ n = 0,1,2,3,4,5...

For n =1 I still get theta to be 90 degrees... I don't see what I'm doing wrong.
 
Your minima formula is wrong.
 
rude man said:
Your minima formula is wrong.

Can you check the post above yours, please ?
 
elemis said:
The formulas listed were in my notes.

Okay, for minima : 2λsinθ = mλ m=0.5,1.5,2.5,3.5...

This would give me the required non-integr half wavelengths for a minima, correct ?

EDIT : Hence m =0.5 would mean the first minima is at 30 degrees.
No. 2sin(theta) = 0.5 does not yield theta = 30 deg.

maxima : 2λsinθ = nλ n = 0,1,2,3,4,5...

For n =1 I still get theta to be 90 degrees... I don't see what I'm doing wrong.

No. 2sin(theta) = 1 does not yield theta = 90 deg.
 
rude man said:
No. 2sin(theta) = 0.5 does not yield theta = 30 deg.



No. 2sin(theta) = 1 does not yield theta = 90 deg.

Ah, God, silly mistakes... Forgive my lapse in concentration. Its pretty late where I am right now.

I've understood this question now. Thank you.
 

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