Assertion: In projectile motion, the vertical velocity of the particle is continoulsy decreased during its ascending motion.
Reason: In projectile motion downward constant acceleration is present in vertical direction.

Options

A. If both assertion `&` Reason are True `&` the Reason is a corrrect explanation of the Asserion.
B. If both Assertion `&` Reason are True but Reason is not correct explanation of the Assertion.
C. If Assertion is Trie but the Reason is False.
D. If both Assertion `&` Reason are false

Answer

To solve the question, we need to analyze the assertion and the reason provided regarding projectile motion.

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that "In projectile motion, the vertical velocity of the particle is continuously decreased during its ascending motion."
- This is true because as the projectile moves upward, it is acted upon by the force of gravity, which pulls it downwards.

2. **Analyzing the Vertical Motion**:
- When a projectile is launched at an angle, it has both horizontal and vertical components of velocity. The vertical component can be expressed as \( V_y = V \sin(\theta) \), where \( V \) is the initial velocity and \( \theta \) is the angle of projection.
- As the projectile ascends, the vertical velocity decreases due to the acceleration caused by gravity acting in the opposite direction.

3. **Understanding the Reason**:
- The reason states that "In projectile motion, downward constant acceleration is present in the vertical direction."
- This is also true. The acceleration due to gravity (\( g \)) is constant and acts downward throughout the motion of the projectile.

4. **Linking Assertion and Reason**:
- The assertion is true because the vertical velocity decreases due to the constant downward acceleration (gravity).
- The reason supports the assertion by explaining that the downward acceleration is the cause of the decrease in vertical velocity.

5. **Conclusion**:
- Both the assertion and the reason are true, and the reason correctly explains the assertion. Therefore, the correct answer is that both statements are true, and the reason is the correct explanation for the assertion.

### Final Answer:
Both the assertion and the reason are true, and the reason is the correct explanation for the assertion.

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