Respuesta :
Answer:
 w = -101 rad / s
Explanation:
For this exercise we will use Faraday's law
     E = - dФ / dt
where the magnetic flux is
     Ф = B. A = B A cos θ
In this case, the angle between the magnetic field and the normal to the disk is zero, cos 0 = 1, they indicate that the field is constant, let's find the area
       Â
The area rotated by the disk is
     A = ½ r s
if we express the angles in radians
     θ = s / r
     s = r θ
where is the arc supported
     A = ½ r (r θ)
let us substitute in the Faraday equation
     E = - d (B ½ r² θ) / dt
     E = - ½ B r² dθ/dt
the definition of angular velocity is
     w = dθ/dt
     E = - ½ B r² w
      w = - 2E / B r²
let's calculate
     w = - 2 3.86 / (0.0314 1.56²)
     w = -101 rad / s
