Help graphing Vectors in polar form

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The discussion focuses on graphing a vector equation in polar form using Desmos. The user is attempting to graph the equation r = (A cosθ sinθ cscθ - B sinθ cscθ) i + (A cosθ sinθ cscθ + B sinθ cscθ) j, but is unclear on how to proceed due to its vector nature. Participants suggest reviewing LaTeX for clarity and emphasize the need to simplify the expression using trigonometric identities. Additionally, they clarify that polar form typically involves scalar values for r and θ, which differs from the user's vector representation. The conversation concludes with advice to explore parametric functions in Desmos for accurate graphing.
physicsfridayrose
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Homework Statement
I'm doing a project looking at gravitational assists and the change in velocity
for part of it my teacher has told me to graph an equation I have but I'm unsure how to, as it is a vector equation in polar form, with constants I'm going to call them A and B. I am trying to use desmos, but am unsure how to
Relevant Equations
I can't seem to type in LaTeX on here so I put it in my solution
The equation I'm trying to graph on desmos is this with A & B as numbers, but I'm unsure how as it is a vector.

r = (A cosθ sinθ cscθ - B sinθ cscθ) i + (A cosθ sinθ cscθ + B sinθ cscθ) j
 
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Hello, maybe you could make a loot at the LaTeX Guide, it will help us to understand what are you asking.
 
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Gaussian97 said:
Hello, maybe you could make a loot at the LaTeX Guide, it will help us to understand what are you asking.
I've had a look and can't seem to work out where I'm supposed to type in LaTeX but have reorganised the question hope it works better now
 
\vec{r} = (A\cos\theta \sin\theta \csc\theta - B sin\theta csc\theta) \hat{i} + (A cos\theta sin\theta\csc\theta+ B \sin\theta\csc\theta) \hat{j}
 
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Well, if you mean what Dr Transport wrote, you can look at some trigonometry identities to simplify a little your expression.
And what is exactly what you want to draw?
 
physicsfridayrose said:
Homework Statement:: I'm doing a project looking at gravitational assists and the change in velocity
for part of it my teacher has told me to graph an equation I have but I'm unsure how to, as it is a vector equation in polar form, with constants I'm going to call them A and B. I am trying to use desmos, but am unsure how to
Relevant Equations:: I can't seem to type in LaTeX on here so I put it in my solution

The equation I'm trying to graph on desmos is this with A & B as numbers, but I'm unsure how as it is a vector.

r = (A cosθ sinθ cscθ - B sinθ cscθ) i + (A cosθ sinθ cscθ + B sinθ cscθ) j
It's not really clear what you mean by "vector equation in polar form". Polar form is ##r=f(\theta)## where ##r##, the distance from the origin, and ##\theta##, the angle relative to the +##x## axis, are both scalars. You don't have that here. On the righthand side, you have a vector with ##x## and ##y## components. You can tell this by the presence of the unit vectors ##\hat i## and ##\hat j##. On the lefthand side, you should have ##\vec r## (not ##r##) which is equal to ##x\,\hat i + y\,\hat j##.

To make a graph in Desmos, check the help for how to plot parametric functions.
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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