Meaning of gradient and intercept

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The equation for the velocity of a body in circular orbit is expressed as v = √(GM/r). By taking natural logarithms, it can be rearranged to ln v = (1/2)ln(GM) - (1/2)ln(r), which resembles the linear equation y = mx + b. In this context, the gradient (m = -1/2) indicates the relationship between the logarithm of the radius and the logarithm of the velocity, showing that as the radius increases, the velocity decreases. The intercept (c = (1/2)ln(GM)) represents the logarithmic value of the velocity when the radius is at a specific reference point. Understanding these components helps clarify the dynamics of gravitational orbits.
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Homework Statement



The velocity of a body traveling in a circular orbit around another body situated at the centre of
the circle, is given by
v = √(GM/r)
where G is the Universal Gravitational constant, M is the mass
of the central body and r is the radius of the orbit. By taking natural logs (ln) of both sides
rearrange the equation in the form of a straight line equation, with r as the independent variable
and identify the meaning of the gradient and the meaning of the intercept

Homework Equations



v = √(GM/r)

The Attempt at a Solution



ln v = (1/2)ln(GM) - (1/2)lnr

y = ln v
x = lnr
c = (1/2)ln(GM)
m = -1/2

I solved the first part but was unsure as to how to answer this part of the question 'identify the meaning of the gradient and the meaning of the intercept'
 
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kingstar said:

Homework Statement



The velocity of a body traveling in a circular orbit around another body situated at the centre of
the circle, is given by
v = √(GM/r)
where G is the Universal Gravitational constant, M is the mass
of the central body and r is the radius of the orbit. By taking natural logs (ln) of both sides
rearrange the equation in the form of a straight line equation, with r as the independent variable
and identify the meaning of the gradient and the meaning of the intercept


Homework Equations



v = √(GM/r)

The Attempt at a Solution



ln v = (1/2)ln(GM) - (1/2)lnr

y = ln v
x = lnr
c = (1/2)ln(GM)
m = -1/2

I solved the first part but was unsure as to how to answer this part of the question 'identify the meaning of the gradient and the meaning of the intercept'
For the line, y = mx + b, m is the gradient and of course, b is the intercept.

Rewrite the original equation with rational exponents rather than radicals.
 
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