Review Angular Momentum

“Write down something you know about angular momentum.”

This SWBQ is meant to jog students' memories about what they know about angular momentum from introductory physics as preparation for understanding precession and Stern-Gerlach experiments.

Want:

• Vector
• Symbol is $\vec{L}$ or $\vec{S}$
• direction determined by a right hand rule (briefly demonstrate)
• same direction as the angular velocity
• Is conserved if net torque is zero
• $=I\vec{\omega}$
• $\tau_{net} = d\vec{L}/dt$ (prompt for this if none appear) (possible segue SWBQ about calculating torque)
• $=\vec{r}$ x $\vec{p}$ with picture (possible segue SWBQ about calculating cross products)
• Dimensions = energy * time = torque * time = length * momentum = mass length^2/ time

Be on the lookout for:

• confusion/connection with linear momentum
• missing vector symbols
• highlight multiple representations
• “Is conserved” (isn't unless net torque is zero)