Hi, I have a question: If there is a negative charge moving w/a velocity that is 50 degrees counter-clockwise from the +x-axis and a B field in the +z direction, I get that the magnitude of the Magnetic Force=(abs. val of q)(abs. val of v)(abs. val of B)sin(theta), where theta=angle b/t v and B, which is 90 degrees b/c v is perpendicular to B. But, how do you get the direction of the Magnetic Force? I know that F should be pointing down in the fourth quadrant by the right hand rule. The answer manual says that F is 40 degrees clockwise from the +x-axis, but why? Is the reason b/c v and F must be perpendicular?(adsbygoogle = window.adsbygoogle || []).push({});

Thanks,

Elizabeth

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# Homework Help: Magnetic Force direction

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