Which of the following change appreciably when a batsman hits a moving cricket ball ?
A. Shape B. Direction C. Size D. speed

Options

A. A and B
B. B and C
C. A and C
D. B and D

Answer

To solve the question "Which of the following change appreciably when a batsman hits a moving cricket ball?" we need to analyze each option provided: A. Shape, B. Direction, C. Size, and D. Speed.

### Step-by-Step Solution:

1. **Understanding the Scenario**:
- A batsman is facing a moving cricket ball. The ball is coming towards him in a certain direction.

2. **Analyzing the Options**:
- **Option A: Shape**:
- The cricket ball is round and its shape does not change when it is hit by the bat. Therefore, this option is incorrect.
- **Option B: Direction**:
- When the batsman hits the ball, it changes direction. Initially, the ball is moving towards the batsman, and after being hit, it goes in a different direction (towards the boundary). Thus, this option is correct.
- **Option C: Size**:
- The size of the cricket ball remains constant regardless of being hit. It does not change in size. Therefore, this option is incorrect.
- **Option D: Speed**:
- When the batsman hits the ball, the speed of the ball changes. The ball may speed up or slow down depending on how hard the batsman hits it. Thus, this option is correct.

3. **Conclusion**:
- The options that change appreciably when a batsman hits a moving cricket ball are **B (Direction)** and **D (Speed)**. Therefore, the correct answer is B and D.

### Final Answer:
B (Direction) and D (Speed) are the correct options.

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