Solution to task 438 from Chertov´s for extramural stud

Solution to task 438 from Chertov´s for extramural stud

438. The alpha particle, having passed the accelerating potential difference U, began to move in a uniform magnetic field (B = 50mT) along a helical line with a step h = 5 cm and a radius of R = 1 cm. Determine the accelerating potential difference that the alpha particle has passed.