According to the third law of motion , action and reaction

Options

A. always act on the same body
B. always act on different bodies in opposite directions
C. have same magnitude and direction
D. act on either body at normal to each other

Explanation

To solve the question regarding Newton's Third Law of Motion, we need to analyze the options provided in relation to the law itself.

### Step-by-Step Solution:

1. **Understanding Newton's Third Law of Motion**:
According to Newton's Third Law of Motion, for every action, there is an equal and opposite reaction. This means that forces always come in pairs.

2. **Analyzing the Options**:
- **Option A**: "Always act on the same body."
- This is incorrect because action and reaction forces act on two different bodies.
- **Option B**: "Always act on different bodies in opposite direction."
- This is correct. The action force acts on one body, and the reaction force acts on a different body, and they are in opposite directions.
- **Option C**: "Have the same magnitude and direction."
- This is incorrect. While the forces are equal in magnitude, they are in opposite directions, not the same direction.
- **Option D**: "Act on either body at normal to each other."
- This is incorrect. The action and reaction forces are not necessarily at right angles to each other; they are in opposite directions.

3. **Conclusion**:
Based on the analysis of the options, the correct answer is **Option B**: "Always act on different bodies in opposite direction."

### Final Answer:
The correct option is **B**: "Always act on different bodies in opposite direction."

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