diff --git a/_mental_models/mental-momentum.md b/_mental_models/mental-momentum.md
index fdf82ce..89940c4 100644
--- a/_mental_models/mental-momentum.md
+++ b/_mental_models/mental-momentum.md
@@ -1,17 +1,64 @@
 ---
 layout: mental-model
 name: Mental Momentum
-benefit: Coming soon
-summary: Coming soon
+benefit: Makes it easier to keep going
+summary: Stay on a meaningful problem long enough, and momentum works in your favor.
 prerequisites:
 ---
 
-#### Description
+## Description
 
-A concept is like a vehicle, dept of topic is mass and time spent on topic is velocity. 
+A concept is like a vehicle. The depth of the topic is its mass. The time you spend on it is its velocity. When both increase, momentum builds.
 
-#### Practice
+If you only touch a topic lightly, momentum never forms. If you constantly switch between tasks, you reset velocity back to zero. Each restart requires energy. Each interruption reduces force.
 
+Mental momentum explains why the first part of any deep work session feels heavy. Your mind is accelerating. After a while, thinking becomes smoother. Connections form faster. The problem space becomes familiar. What initially felt complex begins to organize itself. Shallow engagement produces shallow results. Sustained engagement produces depth.
 
+Momentum is not about intensity for a few minutes. It is about staying long enough for the mind to fully enter the problem.
 
-#### Example-1
+Once momentum builds, progress compounds. When it breaks, friction returns.
+
+## Practice
+1. Pick one meaningful problem or concept.
+2. Decide in advance how long you will stay with it (no switching).
+3. Remove distractions.
+4. Track how your clarity improves as time passes.
+
+### Example-1
+
+**Improving matchmaking logic in a game.**
+
+If you spend 20 minutes thinking about it and then switch to emails, momentum resets.
+
+Instead, block 3 uninterrupted hours.
+- Dive into edge cases.
+- Simulate different player scenarios.
+- Refactor assumptions.
+
+After 2–3 hours, solutions start appearing that wouldn’t surface in fragmented thinking.
+
+### Example-2
+
+**Studying for an important exam.**
+
+If you study for 15 minutes, check your phone, then come back later, you keep restarting. It always feels hard.
+
+Instead, study for a full 90-minute session without interruptions.
+- Work through multiple problems.
+- Review mistakes.
+- Connect concepts together.
+
+After a while, the material starts to click. What felt confusing begins to make sense.
+
+### Example-3
+
+**Learning a difficult concept (e.g., a new algorithm or business strategy).**
+
+Reading one article every few days keeps you in restart mode.
+
+Instead, immerse yourself for a full afternoon.
+- Read multiple sources.
+- Take notes.
+- Apply it immediately.
+
+By the end of the session, the concept feels lighter.