variable mass (conceptual)

Question

In rocket propulsion, thrust arises primarily due to:

RankGuru · Accepted Answer

1. **Law of Conservation of Momentum**: In a closed system with no external forces, total momentum remains constant.
2. **Rocket Mechanism**: A rocket expels gases downward at extremely high velocities ($v_{ex}$). This 'Action' carries away backward momentum.
3. **Thrust Calculation**: By Newton's Third Law, the exhaust gases exert an equal and opposite force (Thrust) on the rocket fuel chamber: $F = v_{ex} (\frac{dm}{dt})$.
4. **Correction**: Rocket propulsion does NOT require air; it works best in a vacuum. It is purely an internal action-reaction process.

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variable mass (conceptual)

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