Game Development Reference
F IGURE 14.1
The rotational and linear components of a collision.
and the angular component by the torque
p f ×
where the torque generates angular acceleration by
I − 1 τ
which is equation 10.3 from chapter 10.
In the case of the collision it stands to reason that the collision will generate a
linear change in velocity (the impulse) and an angular change in velocity. An instan-
taneous angular change in velocity is called an “impulsive torque” (also rarely called
“moment of impulse” or “impulsive moment,” which sounds more like a drunken
Vegas wedding to me). 1
for torques we have
1. Strictly speaking, what we've called impulse is “impulsive force.” We could also call it “linear and an-
gular impulse,” but I'll continue to use just “impulse” to refer to the linear version.