Movement Along & Shift in Demand Curve
Class 11 Micro Economics — Understanding when the curve moves versus when the entire curve changes position
Movement Along the Demand Curve
Movement occurs when the price of the commodity itself changes, keeping other factors constant. The consumer moves from one point to another on the same demand curve.
Click price points on the curve
Expansion (Extension) in Demand
Price falls from ₹3 to ₹2 → quantity demanded rises from 3 to 4 units.
Downward movement along the same demand curve DD.
Summary Table
Shift in Demand Curve
A shift occurs when factors other than own-price change. The entire demand curve moves to a new position.
Base Demand Curve
Toggle Factors
Causes of Rightward Shift (Increase)
Causes of Leftward Shift (Decrease)
Movement vs Shift — The Complete Comparison
Movement Along Curve
| Basis | Movement | Shift |
|---|---|---|
| Cause | Own price change | Other factors change |
| Curve | Same curve | New curve position |
| Types | Expansion / Contraction | Increase / Decrease |
| Also called | Change in Qty Demanded | Change in Demand |
Don't Confuse These Pairs!
Expansion vs Increase
Expansion = movement down the same curve (price falls). Increase = rightward shift of entire curve (other factors change).
Contraction vs Decrease
Contraction = movement up the same curve (price rises). Decrease = leftward shift of entire curve (other factors change).
Key Takeaways
- Movement Along Curve = Change in Quantity Demanded. Caused by change in own price only.
- Expansion (Extension): Price falls → downward movement → Qty rises.
- Contraction: Price rises → upward movement → Qty falls.
- Shift in Curve = Change in Demand. Caused by change in other factors.
- Increase: Favorable factor change → rightward shift (DD → D₂D₂).
- Decrease: Unfavorable factor change → leftward shift (DD → D₁D₁).
- Never confuse: Expansion ≠ Increase, Contraction ≠ Decrease.