# Law of Conservation of Angular Momentum

Written by Jerry Ratzlaff on . Posted in Classical Mechanics

Law of conservation of angular momentum states the angular moment of a system of particles around a fixed point is conserved if there is no net external torque around that point.

## law of conservation of angular momentum formulas

 $$\large{ \Rightarrow\; \Delta L = 0 }$$ $$\large{ \Rightarrow\; \Delta L_i = L_f }$$ $$\large{ L = I \; \omega }$$

### Where:

 Units English Metric $$\large{ L }$$ = angular momentum (rotational momentum) $$\large{\frac{lbm-ft^2}{sec}}$$ $$\large{\frac{kg-m^2}{s}}$$ $$\large{ \omega }$$  (Greek symbol omega) = angular velocity $$\large{\frac{deg}{sec}}$$ $$\large{\frac{rad}{s}}$$ $$\large{ L_f }$$ = final angular momentum $$\large{\frac{lbm-ft^2}{sec}}$$ $$\large{\frac{kg-m^2}{s}}$$ $$\large{ L_i }$$ = initial angular momentum $$\large{\frac{lbm-ft^2}{sec}}$$ $$\large{\frac{kg-m^2}{s}}$$ $$\large{ I }$$ = moment of inertia $$\large{ lbm-ft^2 }$$ $$\large{ kg-m^2 }$$