I am really trying hard to pass my IB Physics class, but the homework is just too hard. Please help me with this problem.(adsbygoogle = window.adsbygoogle || []).push({});

In a TV picture tube, an electron in the beam is accelerated by a potential difference of 20,000 V. Then it passes through a region of transverse magnetic field, where it moves in a circular arc with radius 0.12 m. What is the magnitude of the field?

I am not quite sure how to do this, but this is my approach... First... I used V= U/q to find the velocity of the electrons. Then I used r= (mv)/(Bq) to solve for the magnetic field. And I got 3.98 E-3 Tesla.

Thank you in advance.

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# Homework Help: What is the magnitude of the field?

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