Recently, in a test, I had a question involving a magnetic field and an electron. I've attached the diagram. The "X" denote the magnetic field, moving inwards.(adsbygoogle = window.adsbygoogle || []).push({});

So, there's a uniform magnetic field, moving into the plane of the picture, and theres an electron passing over that plane with its motion parallel to the plane. It is shown by (1)

The question is, what happens to the shape of the path of the electron when the speed of the electron is increased? Does its motion match (2), or (3)???

At first, I did the question by intuition. I thought that since the speed has increased, it'll have less change in direction per unit time. So I chose (2).

But later, the formula F = Bqv was pointed out to me, where F=Force, B=Magnetic Field strengthm, q=charge on the electron, v=velocity of the electron. According to this, (3) should be the correct path!

So what is the correct new path and why? Because I still feel it is (2), even though the formula proves otherwise.

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# Homework Help: Moving electron in a uniform magnetic field

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