### Correct Option: B. Out of the page ### Detailed Explanation: To determine the direction of the magnetic force experienced by a straight current-carrying conductor in a magnetic field, we can use the **right-hand rule**. This is a fundamental concept in electromagnetism that helps visualize the relationship between current, magnetic field, and force. #### Step-by-Step Explanation: 1. **Identify the Directions**: - The current is flowing to the **right**. - The magnetic field is directed **upwards**. 2. **Apply the Right-Hand Rule**: - Extend your right hand. - Point your thumb in the direction of the current (to the right). - Point your fingers in the direction of the magnetic field (upwards). - Your palm will then face outwards, which indicates the direction of the magnetic force. 3. **Conclusion**: - According to the right-hand rule, the magnetic force acting on the conductor will be directed **out of the page** towards you. ### Why the Other Options are Incorrect: - **Option A: To the left**: - This option suggests that the force would act in the opposite direction of the current. However, the right-hand rule clearly shows that the force is not to the left when the current is to the right and the magnetic field is upwards. - **Option C: Into the page**: - This option would imply that the force is directed away from you, which contradicts the application of the right-hand rule. The palm of your hand faces outwards, not inwards. - **Option D: Downwards**: - This option suggests that the force would act in the same direction as gravity. However, the right-hand rule indicates that the force is perpendicular to both the current and the magnetic field, which is not downward in this scenario. ### Formulas and Concepts: - The magnetic force \( F \) on a current-carrying conductor can be calculated using the formula: \[ F = I \cdot L \cdot B \cdot \sin(\theta) \] where: - \( F \) is the magnetic force, - \( I \) is the current, - \( L \) is the length of the conductor, - \( B \) is the magnetic field strength, - \( \theta \) is the angle between the current direction and the magnetic field direction. - In this case, since the current and magnetic field are perpendicular, \( \sin(90^\circ) = 1 \), simplifying the formula to: \[ F = I \cdot L \cdot B \] ### Common Pitfalls: - **Misapplying the Right-Hand Rule**: It's crucial to remember that the thumb represents the current, the fingers represent the magnetic field, and the palm indicates the direction of the force. - **Forgetting the Perpendicular Relationship**: The magnetic force is always perpendicular to both the current and the magnetic field. This is a key aspect of understanding how magnetic forces work. ### Revision Summary: - Use the right-hand rule to determine the direction of the magnetic force on a current-carrying conductor. - The thumb points in the direction of the current, fingers in the direction of the magnetic field, and the palm indicates the force direction. - In this scenario, with current to the right and magnetic field upwards, the force is directed out of the page. - Remember that the magnetic force is always perpendicular to both the current and the magnetic field.