Question

Find the number of oscillations performed per minute by a magnet is vibrating in the plane of a uniform field of 1.6 x 10-5 Wb/m2. The magnet has moment of inertia 3 x 10-6 kg/m2 and magnetic moment 3 A m2.

Answer 1

Given,

uniform magnetic field, B = 1.6 × 10^-5 Wb/m²

moment of inertia of magnet, I = 3 × 10^-6 kg/m²

magnetic moment, M = 3 Am².

To find,

the number of oscillations performed per minutes.

using Time period formula,

T = 2π√{I/MB}

⇒T = 2π√{ 3 × 10^-6/(3 × 1.6 × 10^-5)}

= 2π√{1/16}

= 2π/4 = π/2 sec

therefore time period of magnet is π/2 sec.

we know, number of oscillations per second = 1/time period

= 1/(π/2) = 2/π sec¯¹

then number of oscillations per minute = 60 × 2/π = 120/π min¯¹

Answer 2

Answer:

[Ans: 38.19 occilstions/minute]