Question

The field due to a magnet at a distance R from the centre of the magnet is proportional to

• A. $R ^ { 2 }$
• B. $R ^ { 3 }$
• C.
• D. $1 / R ^ { 3 }$

Answer 1

Answer: (D)

$1 / R ^ { 3 }$

Answer 2

Provided length of magnet is <<the distance.

$B \propto \frac { 1 } { R ^ { 3 } }$