please solve these problems with steps one by one---Here is the extraction of the content from the image: **Question 9** **Question Stem:** A loop of wire lies in a magnetic field directed into the plane of the page. The loop carries a current in a clockwise direction. The magnetic force acting on the wire tends to **Chart/Diagram Description:** * **Type:** 2D diagram with coordinate axes (X and Y) and a circular loop of wire. * **Coordinate Axes:** Horizontal axis labeled X, pointing to the right. Vertical axis labeled Y, pointing upwards. The origin is at the center of the loop. * **Shape:** A circle representing the loop of wire is centered at the origin. * **Current Direction:** An arrow on the circle indicates the current flows in a clockwise direction. * **Magnetic Field:** Represented by symbols (circles with crosses inside) distributed inside and outside the loop. The symbol '⊗' (circle with a cross) indicates the magnetic field is directed into the plane of the page. There are multiple such symbols arranged around and within the loop's area. **Options:** A. rotate the loop about the X axis. B. rotate the loop about the Y axis. C. reduce the radius of the loop. D. increase the radius of the loop. **Question 10** **Question Stem:** When a wire with an electric current I is placed in a magnetic field of strength B it experiences a magnetic force F. What is the direction of F? **Options:** A. In a direction determined by I only B. In a direction determined by B only C. In the plane containing I and B D. At 90° to the plane containing I and B

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Let's analyze Question 9. We have a circular loop of wire in a magnetic field directed into the page, carrying a clockwise current. We need to determine what the magnetic force tends to do to this loop. Using the right-hand rule, we analyze the force on each segment of the wire. Point your fingers in the direction of current flow, curl them toward the magnetic field direction, and your thumb points in the force direction. For each segment, the current is tangent to the loop, the field is into the page, and the resulting force points radially inward toward the center. The conclusion is clear: since all magnetic forces point radially inward toward the center of the loop, the net effect is to compress the loop. This compression tends to reduce the radius of the loop. Therefore, the answer to Question 9 is C: reduce the radius of the loop. Let's analyze Question 9. We have a circular loop of wire carrying current in a clockwise direction, placed in a magnetic field directed into the plane of the page. To understand the force, we need to apply the right-hand rule to each segment of the wire. The magnetic force on a current-carrying conductor is given by F equals I L cross B. Now let's analyze the force on each segment of the loop. Using the right-hand rule: point your fingers in the direction of current, curl them into the magnetic field direction, and your thumb shows the force direction. The top segment experiences a force outward, the bottom segment inward, the left segment downward, and the right segment upward. Looking at the net effect of all forces: the forces on opposite segments cancel each other out in both horizontal and vertical directions, so there's no rotation. Instead, all forces point radially outward from the center of the loop. This means the magnetic force tends to expand the loop, increasing its radius. Therefore, the answer is D. Now let's analyze Question 10. When a current-carrying wire is placed in a magnetic field, the force is given by the cross product formula: F equals I L cross B. The key insight is that the cross product of two vectors always produces a vector perpendicular to the plane containing the original vectors. Therefore, the force F is at 90 degrees to the plane containing the current direction I and the magnetic field B. The answer is D. To summarize: The magnetic force on a current-carrying wire is given by F equals I L cross B. The direction follows the right-hand rule, and the force is always perpendicular to the plane containing the current and magnetic field vectors. For Question 9, the inward radial forces compress the loop, reducing its radius - answer C. For Question 10, the cross product ensures the force is at 90 degrees to the plane containing I and B - answer D.