From 40acb8eb43da41d89a65cd341df4017037db8abc Mon Sep 17 00:00:00 2001 From: eggy Date: Wed, 11 Nov 2020 12:21:34 -0500 Subject: [PATCH] phys: conservation of momentum? --- docs/sph3u7.md | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/docs/sph3u7.md b/docs/sph3u7.md index 9d1c73f..ca1dac7 100644 --- a/docs/sph3u7.md +++ b/docs/sph3u7.md @@ -508,6 +508,14 @@ As momentum is a **vector**, it must have a direction, and these differences in !!! example Bouncing balls change direction, so one of the velocities is in a direction opposite of the other. +### Conservation of momentum + +Assuming there are no external forces, or if they are negligible, momentum between two objects must be conserved: +$$\Sigma\vec{P}_i=\Sigma\vec{P}_f$$ + +When two objects collide, their momentums must be equal and opposite if they travel in opposite directions: +$$-\Delta\vec{P}_A = \Delta\vec{P}_B$$ + ### Impulse Impulse is the change in momentum of an object because of a force. It is expressed mathematically as $\vec{J}$, and is also represented in Newton seconds.