Energy is 4 *
J
The rate of dissipation is 2 *
W
In the question, it is given that
t = 20 s
R = 400 mm
L = 300 mm
where t, R, and L are time, radius, and length.
For magnetic energy density, the formula is
ηo = Energy / volume
= β^2 / 2 * μ
Now, substituting the values
=
/ 2 * 4 * Π * 
= 1.59 *
J / m^3
Now, energy is
= energy density * volume
= 1.59 *
* Π * 0.5 * 
= 4 *
J
The rate of dissipation is
= Energy / time
= 4 *
/ 20
= 2 *
W
For more information click on the link below:
brainly.com/question/7802337
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