The armature of a small generator consists of a flat, square coil with 150 turns and sides with a length of 2.00 cm. The coil rotates in a magnetic field of 8.20×10−2 T. What is the angular speed of the coil if the maximum emf produced is 2.50x10^-2?

Respuesta :

Answer:

Angular speed of the coil 5.08 rad/s

Solution:

As per the solution:

No. of turns, N = 150 turns

Length of the coil, l = 2.00 cm

Magnetic field, B = [tex]8.20\times 10^{- 2}\ T[/tex]

Maximum emf, [tex]e_{max} = 2.50\times 10^{- 2}[/tex]

Now,

[tex]\phi = BAcos\omega t[/tex]

Instantaneous emf, [tex]e = -N\frac{d\phi}{dt}[/tex]

where

[tex]\phi [/tex] = flux

[tex]\omega [/tex] = angular speed

[tex]e = -N\frac{d(BAcos\omega t)}{dt}[/tex]

[tex]e =  N\omega (BAsin\omega t)[/tex]

Maximum emf is obtained at [tex]sin90^{\circ}[/tex]

[tex]e_{max} = BAN\omega [/tex]

[tex]\omega = \frac{e_{max}}{BAN}[/tex]

[tex]\omega = \frac{2.50\times 10^{- 2}}{8.20\times 10^{- 2}\times 0.02^{2}\times 150} = 5.08\ rad/s[/tex]

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