IOM 2017, Блиц — Задача 51

OLYMPIAD OF METROPOLISES. Moscow, September 4 · 4 септември 2017 г.

Условие

A parallel monochromatic electron beam strikes a metal sphere of radius R=10R = 10 cm. Assume that the sphere charge equals half the maximum charge to which the sphere is eventually charged by the given beam.

Determine the maximum distance bb from the axis passing through the sphere centre and parallel to the incident beam at which the electrons still reach the sphere. (The distance bb is measured far away from the sphere where electron velocities are parallel.) Give the answer in centimeters.

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.

A shaded sphere with radius R drawn as an arrow from its centre; a dashed horizontal axis through the centre; on the right, electrons (dots) moving left with arrows, with the distance b marked between the axis and one electron path.

Отговори

Решение

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