======Magnetic Force and Separation Distance======


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**Alternative titles:** Inverse Square Law of Magnetism
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====Summary====                   
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====Procedure====  
  - Set up two bar magnets so that their poles face each other at varying distances.  
  - Use a force sensor, spring balance, or similar method to measure the magnetic force at each separation distance.  
  - Record force readings at several different distances.  
  - Plot force versus distance on standard graph paper to see the relationship.  
  - Re-plot data using logarithmic scales (log(force) vs. log(distance)) to identify whether the data follows an inverse square law or another power relationship.  
  - Determine the slope of the line from the log-log graph to find the exponent in the power law.



====Links==== 
Magnetic force and separation distance #2 (NCPQ) - Dr Richard Walding: 
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====Variations====
  * Try measuring repulsive forces (like poles facing) instead of attractive forces.  
  * Compare results with different types or sizes of magnets.  
  * Repeat with magnets aligned in different orientations (end-to-end vs. side-by-side).



====Safety Precautions====
  * Handle strong magnets carefully to avoid pinching fingers.  
  * Keep magnets away from electronic devices, magnetic storage, and credit cards.  
  * Avoid dropping magnets, as they may chip or shatter.




====Questions to Consider====
  * What relationship exists between force and separation distance? (It follows a power law, close to an inverse square.)  
  * Why does the log-log graph give a straight line? (Because a power law appears linear when both variables are plotted on logarithmic scales.)  
  * How does this compare to gravitational or electrostatic forces? (They both follow an exact inverse square law, F ∝ 1/r².)  
  * What might cause deviations from the exact inverse square law in this experiment? (Magnet imperfections, finite magnet size, alignment issues, or measurement errors.)