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An electron experiences no deflection when the force from the electric field matches the force from the magnetic field. This occurs when q|E| = q|v̅||B|, leading to |v̅| = |E| / |B|. What is the resulting motion of the electron?

1. The electron travels along a straight path.
2. The electron follows a circular trajectory.
3. The electron traces a helical path.
4. The electron stays at rest.

Correct answer: The electron travels along a straight path.

Solution

For the electron to move undeflected, the electric force and magnetic force must cancel each other out. This condition ensures that the net force on the electron is zero, resulting in straight-line motion.

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