Multiple Choice

An electron is moving along the positive $$X$$-axis. You want to apply a magnetic field for the short time so that the electron may reverse its direction and move parallel to the negative $$X$$-axis. This can be done by applying the magnetic field along :

A$$Y$$-axis
Correct Answer
B$$Z$$-axis
Correct Answer
C$$Y$$-axis only
D$$Z$$-axis only

Solution

Force on charged particle due to magnetic field is
$$F = q(\vec v \times \vec B)$$
Hence, to reverse the direction of electron from positive X-axis to the direction parallel to the negative X-axis, magnetic field should be applied along Y-axis or Z-axis.

SIMILAR QUESTIONS

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