Velocity Selector: a Beam of Electrons Is Accelerated Through a Potential

question 48

Multiple Choice

Velocity selector: A beam of electrons is accelerated through a potential difference of 10 kV before entering a region having uniform electric and magnetic fields that are perpendicular to each other and perpendicular to the direction in which the electron is moving. If the magnetic field in this region has a value of 0.010 T, what magnitude of the electric field is required if the particles are to be undeflected as they pass through the region?

• A) 2.3 × 10³ V/m
• B) 7.9 × 10³ V/m
• C) 5.9 × 10⁵ V/m
• D) 6.0 × 10⁵ V/m
• E) 7.2 × 10⁶ V/m

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Definitions:

Problem-focused Coping

A strategy for managing stress by directly tackling the problem that is causing emotional distress.

Emotion-focused Coping

A strategy aimed at managing the emotional response to a stressful situation rather than confronting the root of the problem directly.

Behavioral Focusing

A technique used to help individuals concentrate on specific behaviors for the purpose of changing them, typically used in therapeutic settings.

Cognitive Adaptation

The mental process of adjusting perceptions, thoughts, and behaviours to deal with new information or experiences.