Which of the following laws of conservation is used in the propulsion of rockets?
Correct answer: D. Momentum
- A. Heat
- B. Mass
- C. Energy
- D. Momentum
Explanation
The correct answer is Momentum. Rocket propulsion is explained by Newton's third law of motion: for every action, there is an equal and opposite reaction. When a rocket expels gas downwards, the momentum lost by the gas is gained by the rocket, propelling it upwards. This is a direct application of the conservation of momentum. The other options are incorrect because:Heat: While heat is generated and plays a role in energy transfer, it does not directly govern the propulsion mechanism of rockets.Mass: Mass is a component of the momentum equation, but the conservation principle used is momentum, not mass.Energy: Energy conservation is relevant in rocket science, but it is not the principle specifically used to explain propulsion.
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About Linear Momentum
Linear momentum is the vector product of mass and velocity, p = mv, and changes when a net external force acts. Work includes impulse as the change in momentum, conservation of momentum in isolated systems, collisions and explosions, and the distinction between elastic, inelastic and perfectly inelastic collisions.
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