The principle involved in the working of Rocket is

Options

A. Newton's laws of motion
B. Bernoulli's principle
C. Photoelectric effect
D. Faraday's laws of EMI

Answer

**Step-by-Step Solution:**

1. **Understanding Rocket Motion**: A rocket operates based on the principle of action and reaction. When a rocket is launched, it expels gas at high speed in one direction.

2. **Application of Newton's Third Law**: According to Newton's Third Law of Motion, for every action, there is an equal and opposite reaction. This means that when the rocket pushes the gas downwards (action), the gas pushes the rocket upwards (reaction).

3. **Force Exerted**: Let’s denote the force exerted by the rocket on the gas as \( F \). By Newton's Third Law, the gas exerts an equal force \( F \) back on the rocket in the opposite direction.

4. **Resulting Motion**: The upward force acting on the rocket due to the expelled gas is what propels the rocket into the sky. This upward force must overcome the gravitational force acting on the rocket for it to ascend.

5. **Conclusion**: Therefore, the principle involved in the working of a rocket is primarily based on Newton's Third Law of Motion.

**Final Answer**: The principle involved in the working of a rocket is Newton's Third Law of Motion.

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