Physics Lab / Equation manipulation

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The discussion revolves around the manipulation of the equation T^2 = (4 pi^2 m)/k * d^2 + (4 pi^2 I)/k, where T^2 is plotted against d^2. The equation's parameters include a gradient (m) and a y-intercept (c), with the challenge being the determination of constants k and I when the mass (m) is unknown. Participants clarify that 'm' serves dual roles: one as the measured mass and the other as the slope of the plotted data. To find k and I, both the measured mass and the slope from the graph are necessary. Understanding these relationships is crucial for accurate calculations in the lab titled "Oscillation of a metre rule."
Greg3Dot
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1. T^2 = (4 pi^2 m)/k * d^2 + (4 pi^2 I)/k
y = m * x + c
Information
(4 pi^2 m)/k = m (gradient)
(4 pi^2 I)/k = c (the y intercept )
A graph of T^2 vs d^2 was plotted.
(^2) means squared
Find constants k and I
How is this done since the m in the formula is unknown ?
"Oscillation of a metre rule" is the the tiltle of the lab
 
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Greg3Dot said:
1. T^2 = (4 pi^2 m)/k * d^2 + (4 pi^2 I)/k
y = m * x + c
Information
(4 pi^2 m)/k = m (gradient)
(4 pi^2 I)/k = c (the y intercept )
A graph of T^2 vs d^2 was plotted.
(^2) means squared
Find constants k and I
How is this done since the m in the formula is unknown ?
"Oscillation of a metre rule" is the the title of the lab
It looks like you have 'm' serving two different roles.

The 'm' I highlighted in red above appears to be the mass of something. Presumably you measured it.

The other m, should be the slope (gradient) of the data you graphed, which hopefully fell along some line. This m together with c, should allow you to determine I and k, but you will need to know m .
 
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SammyS said:
It looks like you have 'm' serving two different roles.

The 'm' I highlighted in red above appears to be the mass of something. Presumably you measured it.

The other m, should be the slope (gradient) of the data you graphed, which hopefully fell along some line. This m together with c, should allow you to determine I and k, but you will need to know m .[/Q
Thanks a lot , there was a mass that was measured.
 
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