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:
Correct answer: B. T/n
- A. T
- B. T/n
- C. Tn
- D. 1/Tn
Explanation
T = 2π √(I / MB)on breaking n equal parts perpendicular to lengthI' = (1/12) (m/n) (ℓ/n)² of each partI' = I / n³ , M' = M / nT' / T = √[(I' / M') × (M / I)] = √[(1/n³ × n) / 1] = 1/n ⇒ T' = T / n
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Magnetic flux density and magnetic flux describe the strength of a magnetic field and the field passing through a surface. A charged particle moving through a magnetic field experiences a force perpendicular to its velocity and may follow circular or helical motion, depending on the angle between velocity and field.
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