Question

A magnetic needle of negligible breadth and thickness compared to its length, oscillates in a horizontal plane with a period T. The period of oscillation of each part obtained on breaking the magnet into n equal parts and perpendicular to the length is –

• A. T
• B. T/n
• C. Tn
• D. 1Tn

Answer 1

Answer: (B)

T/n

Answer 2

T = 2π

on breaking n equal parts perpendicular to length

I' = $\frac { 1 } { 12 }$ of each part

I' = , M^' =

$\sqrt { \frac { \mathrm { I } ^ { \prime } } { \mathrm { M } ^ { \prime } } \times \frac { \mathrm { M } } { \mathrm { I } } }$= = ⇒ T' =