Statement (A) : Moving charges produce not only an electric field but also magnetic field in space
Statement (B) : The force is exerted by a magnetic field on moving charges or on a current carrying conductor only but not on stationary charges

Options

A. A is a true B is false
B. A is false B is true
C. A and B are true
D. A and B is false

Answer

To determine the truth of the statements provided in the question, we can analyze each statement step by step.

### Step 1: Analyze Statement A
**Statement A:** "Moving charges produce not only an electric field but also a magnetic field in space."

- **Explanation:** According to electromagnetic theory, a charge at rest produces only an electric field. However, when a charge is in motion, it generates both an electric field and a magnetic field. This is a fundamental principle in physics, particularly in the study of electromagnetism.

- **Conclusion:** Statement A is **True**.

### Step 2: Analyze Statement B
**Statement B:** "The force is exerted by a magnetic field on moving charges or on a current-carrying conductor only but not on stationary charges."

- **Explanation:** The force exerted by a magnetic field on a charge is given by the Lorentz force law, which states that the force \( \mathbf{F} \) on a charge \( Q \) moving with velocity \( \mathbf{v} \) in a magnetic field \( \mathbf{B} \) is given by:
\[ \mathbf{F} = Q(\mathbf{v} \times \mathbf{B}) \]
If the charge is stationary, its velocity \( \mathbf{v} \) is zero. Therefore, the force \( \mathbf{F} \) will also be zero. This means that a magnetic field does not exert a force on stationary charges.

- **Conclusion:** Statement B is **True**.

### Final Conclusion
Both statements A and B are true. Therefore, the correct answer is that both statements are true.