To become familiar with the order of magnitude of magnetic effects, consider the situation in a television cathode ray tube (not a flat-panel TV). In order to bend the electron trajectory so that the...

To become familiar with the order of magnitude of magnetic effects, consider the situation in a television cathode ray tube

(not a flat-panel TV). In order to bend the electron trajectory so that the electron hits the top of the screen rather than going

straight through to the center of the screen, you need a radius of curvature in the magnetic field of about 20 cm (Figure

21.80). If the electrons are accelerated through a 15,000-volt potential difference, they have a speed of 0.7 × 108 m/s.

Calculate the magnitude of the magnetic field required to make the electrons hit the top of the screen. Is the magnetic field

into or out of the page?