1. Write out the vector V=2i+3j at the point (x,y) = (1,2) in terms of the unit vectors in plane polar coordinates. Do this again for the same vector at the origin. Are your results different? Why?(adsbygoogle = window.adsbygoogle || []).push({});

Answer:

From my notes, I see that x,y = (r, theta) and x=r cos theta, y=r sin theta.

So, for (1,2) the vector is 2 cos 2 i + 3 sin 2 j

At the origin, (0,0), the vector is zero. Am I on the right track?

2.Find the gradient of the function phi(x,y)=2x^2y at the point (x,y)=(1,2), in plane polar coordinates.

Answer:

The gradient is 4xyi+2x^2j. At (1,2) it's 8i+2j. How would I put it in plane polar cooridnates? Would the answer be (8 cos 2) i + (2 sin 2) j?

Thanks.

**Physics Forums - The Fusion of Science and Community**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# 2 vector problems(am i doing them right)

Loading...

Similar Threads for vector problems doing | Date |
---|---|

I A question about Vector Analysis problems | Oct 4, 2017 |

I Complex integral problem | Dec 7, 2016 |

Kleppner/Kolenkow Vector Problem | Dec 17, 2015 |

Vector Calculus Problem | Jan 22, 2015 |

Integration by parts problem involving vector functions | Aug 9, 2013 |

**Physics Forums - The Fusion of Science and Community**