IOM 2018, Блиц, английски — Задача 57

OLYMPIAD OF METROPOLISES. Moscow, September 3 · 3 септември 2018 г.

Условие

A ring of a radius $r = 0.5$ m is made of a wire of a diameter $d = 1$ mm and a resistivity of $\rho = 0.1$ Ohm·mm$^2$/m. The ring is placed in a varying uniform magnetic field which is perpendicular to the ring plane. The magnetic induction increases at a constant rate from zero to $B = 1$ T in $t_1 = 4$ s, then it decreases at a constant rate from $B$ to $B/2$ in $t_2 = 1$ s. How much heat will be generated in the ring during the whole process? Give the answer in mJ.

The answer should be given in the SI units unless otherwise stated. If the numerical result turns out to be an integer, it should be given as the answer. Otherwise round the result to the first decimal. $g = 10\ \mathrm{m/s^2}$.

Отговори

Решение

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Оригинал в Архива: blitz.pdf · официални решения: blitz-answers.pdf