- #1

Krushnaraj Pandya

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## Homework Statement

A particle (5 kg) moves with constant velocity 2 m/s along the straight line 2y=3x+4, the angular momentum of the particle about origin is?

## Homework Equations

L=r x p

## The Attempt at a Solution

For a 2d problem we take the component of velocity perpendicular to the point about which we want to find the momentum and multiply it with the perpendicular distance. Here slope of the line gives tanθ=3/2, p=mv=10 and L=mvrcosθ, mvcosθ equals 20/√13 but isn't the distance r (here r=the y coordinate of the particle) continuously increasing? I get the correct answer for r=2 though, I don't understand how. I'd really appreciate some help, thank you