Real-World Examples of Magnetic Pole Attraction and Repulsion

📚 Quick Study Guide

• 🧲 Magnetic poles always exist in pairs: North and South.
• 🍎 Like poles (North-North or South-South) repel each other.
• 🧭 Opposite poles (North-South) attract each other.
• 🌐 The strength of the magnetic force decreases with distance. This force is described by Coulomb's Law for magnetism: $F = \frac{{\mu q_1 q_2}}{{4 \pi r^2}}$, where $F$ is the force, $\mu$ is the permeability of the medium, $q_1$ and $q_2$ are the magnetic pole strengths, and $r$ is the distance between the poles.
• ⚡ Magnetic fields are created by moving electric charges (like in electromagnets).
• ✨ Earth itself has a magnetic field, which is crucial for navigation and protecting us from solar wind.

Practice Quiz

1. Which of the following statements is true about magnetic poles?
   1. A) Like poles attract each other.
   2. B) Opposite poles repel each other.
   3. C) Magnetic monopoles (isolated North or South pole) are commonly found.
   4. D) Opposite poles attract each other.
2. What happens when two magnets are brought close together with their North poles facing each other?
   1. A) They attract.
   2. B) They repel.
   3. C) They spin around each other.
   4. D) Nothing happens.
3. An electromagnet is created by:
   1. A) Placing two permanent magnets near each other.
   2. B) Running an electric current through a wire.
   3. C) Heating a piece of iron.
   4. D) Cooling a piece of aluminum.
4. How does the strength of the magnetic force change as the distance between two magnets increases?
   1. A) It increases linearly.
   2. B) It decreases linearly.
   3. C) It increases exponentially.
   4. D) It decreases exponentially.
5. Which of the following uses the principle of magnetic attraction and repulsion?
   1. A) A compass.
   2. B) A light bulb.
   3. C) A wooden chair.
   4. D) A glass window.
6. Earth's magnetic field protects us from:
   1. A) Acid rain.
   2. B) Solar wind.
   3. C) Global warming.
   4. D) Volcanic eruptions.
7. In the formula $F = \frac{{\mu q_1 q_2}}{{4 \pi r^2}}$, what does 'r' represent?
   1. A) The magnetic force.
   2. B) The permeability of the medium.
   3. C) The distance between the poles.
   4. D) The magnetic pole strength.