Multiple choice, magnetic force on the particle

AI Thread Summary
The discussion centers on a physics problem involving the magnetic force on a charged particle. The user calculates the force using the formula F=qV×B, noting that the negative charge affects the direction of the force. Despite their calculations leading to a force vector of (20i-15j), they express confusion about why the answer is labeled as D. The user questions whether their approach is correct and seeks clarification on the cross product involved in the equation. The thread highlights the complexities of applying the right-hand rule and vector cross products in magnetic force calculations.
Mdhiggenz
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Homework Statement



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Homework Equations





The Attempt at a Solution



I know that since the charge is negative qo*Vperpendicular would be traveling in the oppsite direction. Which by the right hand rule ultimately affects B.

So using the formula F=q0V(perpendicular)*B

= 1*5(4i-3j)
= (20i-15j)

I don't understand why the answer would be D.

Or maybe my approach to the problem was incorrect?

Thanks
 
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