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In fact I know the answers of this problem, but I have a question.

Here's the question.

A charge +q moving with constant velocity v enters into a uniform magnetic field region as shown. The magnetic flux density is B.

a) What is the direction of the force F experienced by q?

b) What is the work done by F?

c) What kind of motion it is performing?

d) Express the radius of curvature r of the change in terms of B, v, m and q. Where m is the mass of the charge.

ans:

a) Direction of force is always perpendicular to the direction of q. The point charge will go upward.

From the part (d), I know it is performing circular motion and that the work done by F is 0 J!

d) r = mv/(Bq)

Why it is performing circular motion? Can't it be an elliptical motion?

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# Interesting Magnetism Problem

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