Calculate L using Omega, Lo = 16, and h = 1.5

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Homework Help Overview

The discussion revolves around finding the value of L using the equation involving omega, Lo, and h, specifically with given values of omega = -2.6, Lo = 16, and h = 1.5. The subject area includes logarithmic functions and algebraic manipulation.

Discussion Character

  • Mathematical reasoning, Problem interpretation

Approaches and Questions Raised

  • Participants discuss the algebraic manipulation of the equation to isolate L. There are attempts to clarify the correct notation for the natural logarithm and suggestions on the order of substituting constants to avoid round-off errors.

Discussion Status

Some participants have provided guidance on notation and algebraic steps, while others have reiterated the importance of proper abbreviation. Multiple interpretations of the algebraic process are being explored, but there is no explicit consensus on a single method.

Contextual Notes

There is a mention of potential round-off errors when substituting constants early in the calculations, indicating a concern for accuracy in the problem-solving process.

eddievic
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Find L if...

Homework Statement



[tex]\omega=\frac{1}{h}In(\frac{L}{Lo}-1)[/tex]

Find L if omega - -2.6, Lo = 16 and h = 1.5

Homework Equations





The Attempt at a Solution



-2.6*1.5=In(L/16-1)
-3.9=In(L/16-1
e^-3.9=L/16-1
0.02024=L/16-1
1.02024=L/16
so L=16.32384
 
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The correct abbreviation for the natural log is 'lower case L' and 'lower case N'. You have 'Upper case I' and 'lower case N', which is incorrect. Otherwise, your algebra appears to be correct.
 
SteamKing said:
The correct abbreviation for the natural log is 'lower case L' and 'lower case N'. You have 'Upper case I' and 'lower case N', which is incorrect. Otherwise, your algebra appears to be correct.

Ok thanks for the help I will use the correct abbreviation in future
 
eddievic said:

Homework Statement



[tex]\omega=\frac{1}{h}In(\frac{L}{Lo}-1)[/tex]

Find L if omega - -2.6, Lo = 16 and h = 1.5

Homework Equations


The Attempt at a Solution



-2.6*1.5=In(L/16-1)
-3.9=In(L/16-1
e^-3.9=L/16-1
0.02024=L/16-1
1.02024=L/16
so L=16.32384

It's best to substitute the constants at the end of your algebraic manipulation. Doing so sooner can lead to round-off errors.

This is the way I would have done it.
$$\omega=\frac{1}{h}\ln(\frac{L}{L_0}-1)$$
$$\Rightarrow h \omega = \ln(\frac{L}{L_0}-1)$$
$$\Rightarrow e^{h \omega} = \frac{L}{L_0}-1$$
$$\Rightarrow e^{h \omega} + 1 = \frac{L}{L_0}$$
$$\Rightarrow L_0 (e^{h \omega} + 1) = L$$
Now you can replace the constants.
 
Mark44 said:
It's best to substitute the constants at the end of your algebraic manipulation. Doing so sooner can lead to round-off errors.

This is the way I would have done it.
$$\omega=\frac{1}{h}\ln(\frac{L}{L_0}-1)$$
$$\Rightarrow h \omega = \ln(\frac{L}{L_0}-1)$$
$$\Rightarrow e^{h \omega} = \frac{L}{L_0}-1$$
$$\Rightarrow e^{h \omega} + 1 = \frac{L}{L_0}$$
$$\Rightarrow L_0 (e^{h \omega} + 1) = L$$
Now you can replace the constants.

this makes a lot of sense thanks Mark44
 

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