Great set of questions! Here are detailed answers for each: --- **4. Floating Compass Needle: Will it float toward the north side of the bowl?** **No, the needle will not float toward the north side of the bowl.** The compass needle aligns itself with the horizontal component of Earth's magnetic field, so it rotates to point north-south, but the **magnetic field does not exert a force that pulls the needle northward across the water**. It only causes a **torque** that makes the needle align with the field. The needle will remain in the same place on the surface of the water, just oriented north-south. --- **5. Compass Needle Near a Horizontal Current-Carrying Wire (South to North):** When a current flows **south to north** in a horizontal wire: - **Above the wire:** Use the right-hand rule. Point your thumb north (current), your fingers curl around the wire. Above the wire, the magnetic field points **east**. - **Below the wire:** The magnetic field points **west**. So, **above** the wire, the compass needle points **east**; **below** the wire, it points **west.** --- **6. Cosmic Radiation in Northern Canada vs. Mexico:** Residents of northern Canada are bombarded by more intense cosmic radiation than residents of Mexico because **Earth's magnetic field deflects charged cosmic rays toward the poles**. Near the equator, the magnetic field is more effective at deflecting these particles, so **less radiation reaches the surface**. Near the poles, cosmic rays can penetrate more easily because the field lines are nearly vertical, so **more radiation reaches the surface**. --- **7. Compass Needle Near the North Magnetic Pole:** If a compass needle were free to point in **all directions**, near Earth's north magnetic pole in Canada, the needle would point **straight down**. This is because the Earth's magnetic field at the pole is directed nearly vertically into the ground. --- **8. Compass Across the Equator—Does It Reverse Direction?** Your first friend is **wrong**: A compass does **not** turn around and point in the opposite direction when you cross the equator. Your second friend is also **incorrect** about people using the "south magnetic pole" of the compass. **Here’s the correct explanation:** A compass needle always points toward the Earth's magnetic north pole, regardless of hemisphere. The "north" end of the compass needle is attracted toward what we call the Earth's north magnetic pole (which is actually a magnetic south pole). **People in both hemispheres use the north end of the compass to find geographic north.** The compass does not flip around at the equator. --- If you’d like further details or illustrations for any of these answers, let me know!