chetzread
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Homework Statement
why x is p(cosθ)(sinφ) ? and y=p(sinθ)(cosφ)?
z=p(cosφ)
As we can see, φ is not the angle between p and z ...
Triple integral in polar coordinate
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why x is p(cosθ)(sinφ) ? and y=p(sinθ)(cosφ)?
z=p(cosφ)
As we can see, φ is not the angle between p and z ...
Mr-R
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Why would you think that?
Well, as I see it, ##\phi## is the angle between ##z## and ##\rho##.
Well, as I see it, ##\phi## is the angle between ##z## and ##\rho##.
chetzread
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really? then where is p?Mr-R said:
P is on the same line as x-axis, am i right?
Mr-R
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chetzread said:
Nope it is not on the same axis as x. If that was the case then the equation ##x^2+y^2+z^2=\rho^2## wouldn't make sense.
If you are bothered by the provided diagram then just look up another one from another source
Irene Kaminkowa
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https://www.physicsforums.com/members/chetzread.597855/
You had better start from 2D - the polar coordinates, trying to understand, why x = ρ cos Θ and y = ρ sin Θ.
You had better start from 2D - the polar coordinates, trying to understand, why x = ρ cos Θ and y = ρ sin Θ.
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That's a really bad figure. No wonder you're confused. Check out the page ehild linked to.chetzread said:
By the way, ##\rho## is the Greek letter rho. It's not P nor p.
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Can I also point out that physicists use ##\theta## for the polar angle and ##\phi## for the azimuthal angle ?
Much more consistent with the cylindrical ##(\rho,\phi,z)## coordinate system
So: stay alert to avoid miscommunication !
Much more consistent with the cylindrical ##(\rho,\phi,z)## coordinate system
So: stay alert to avoid miscommunication !