A rocket works on the principle of:

Options

A. Newton's first law of motion
B. Newton's second law of motion
C. Newton's third law of motion
D. First law of thermodynamics

Explanation

**Step-by-Step Solution:**

1. **Understanding Rocket Propulsion**: A rocket is a vehicle designed to propel itself into space by expelling gas at high speed from its engines. This process is fundamental to how rockets operate.

2. **Identifying Relevant Laws of Motion**: To understand how a rocket works, we need to consider Newton's laws of motion, particularly the third law.

3. **Newton's Third Law of Motion**: This law states that for every action, there is an equal and opposite reaction. In the context of a rocket, when the rocket's engines expel gas downwards (action), the rocket is pushed upwards (reaction).

4. **Application of the Law**: When the rocket's engines ignite, they produce a high-speed stream of gases that are expelled downward. According to Newton's third law, this action creates an upward force on the rocket itself, allowing it to ascend.

5. **Conclusion**: Therefore, a rocket works on the principle of Newton's third law of motion, which explains the relationship between the action of expelling gas and the reaction of the rocket moving upward.

**Final Answer**: A rocket works on the principle of Newton's third law of motion.

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