A charge q moves with velocity v⃗ in a region containing both electric field E⃗ and magnetic field B⃗. Which expression gives the total Lorentz force?
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A charge q moves with velocity v⃗ in a region containing both electric field E⃗ and magnetic field B⃗. Which expression gives the total Lorentz force?

G1 Physics · Accepted Answer

Step 1: An electric field exerts force F⃗_E = qE⃗ on a charge q. Step 2: A magnetic field exerts force F⃗_B = q(v⃗ × B⃗) on the moving charge. Step 3: By superposition, total Lorentz force is F⃗ = qE⃗ + q(v⃗ × B⃗). Step 4: The order of the cross product matters: B⃗ × v⃗ = −(v⃗ × B⃗). Final answer: (B) qE⃗ + q(v⃗ × B⃗).