The time taken for the magnetic field to change to the given magnitude is 100.0 s.
The concept of induced emf in the loop can be used to determine the rate at which the magnetic field is changing.
[tex]emf =N\frac{d\phi}{dt}[/tex]
where;
Ф = BA
where;
A is area of the loop
A = πr²
A = π(0.5)² = 0.785 m²
[tex]emf = N\frac{dBA}{dt} \\\\emf = NA(\frac{B_2 - B_1}{t} )\\\\t = \frac{NA(B_2 - B_1)}{emf}[/tex]
[tex]t = \frac{10 \times 0.785 \times (2.5 - 0.5)}{0.157} \\\\t = 100.0 \ s[/tex]
Thus, the time taken for the magnetic field to change to the given magnitude is 100.0 s.
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