Concept:The magnetic force acting on a moving charge depends on the cross product of its velocity and the magnetic field. If the charge moves parallel to the magnetic field, no magnetic force acts on it.
Formula:$$ F = qvB \sin(\theta) $$
Solution:- Identify the given values: \( q = 2 \times 10^{-6} \ \text{C} \), \( v = 2 \ \text{m/s} \), \( B = 2 \ \text{T} \).
- Determine the angle \( \theta \): The phrase "in the direction of" means the velocity vector is parallel to the magnetic field vector, so \( \theta = 0^\circ \).
- Calculate the sine of the angle: \( \sin(0^\circ) = 0 \).
- Substitute into the formula: \( F = (2 \times 10^{-6})(2)(2)(0) = 0 \ \text{N} \).
Why other options are incorrect:Options A, C, and D are the results of multiplying the magnitudes while incorrectly assuming \( \theta = 90^\circ \) (which would yield \( 8 \times 10^{-6} \ \text{N} \)) or ignoring the micro prefix.
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