(adsbygoogle = window.adsbygoogle || []).push({}); [SOLVED] Having problem in crossproduct, dotproduct.

Sorry, i have a lil problem in solving for some math in physics equation.

I'm doing simulation of rigid body collision reaction,

and i applied the angular momentum,

which isL = p x r = I ( w2 - w1);

wherep = mvis the impact of the collision,

w1,w2is the angular velocity.

rbe the vector from the center of body to the collision point.

I'm wondering if the eq isp x r,

in a2D system, the third coordinate system is ignored.

and in some circumstances,

i let the equation to be reformed into something likep * n x r,

where n is thereflect/normal vectorat the collision point.

sincep x ris actually the cross-product,

but some books are telling me to take dotproduct of it,

i'm wondering and hoping to seek for help.

Thanks in advance.

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# Having problem in crossproduct, dotproduct.

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