diff --git a/300s School/NUCE 2100 - Fundamentals of Nuclear Engineering/2024-09-17 Module 5 Nuclear Fission Basics.md b/300s School/NUCE 2100 - Fundamentals of Nuclear Engineering/2024-09-17 Module 5 Nuclear Fission Basics.md
index 9eb09d46..52581436 100644
--- a/300s School/NUCE 2100 - Fundamentals of Nuclear Engineering/2024-09-17 Module 5 Nuclear Fission Basics.md	
+++ b/300s School/NUCE 2100 - Fundamentals of Nuclear Engineering/2024-09-17 Module 5 Nuclear Fission Basics.md	
@@ -35,3 +35,4 @@ Rate of increase = Production - absorbed - leakage
 ### Multiplication factor
 $$k = \frac{\text{Number of neutrons in one generation}}{\text{Number of neutrons in preceding generation}}$$
 Measures how many neutrons produced by each neutron born.
+There are more formulas in the slides. K can be based on material properties