An Electron Moves in a Region Where the Magnetic Field

question 71

Multiple Choice

An electron moves in a region where the magnetic field is uniform, has a magnitude of 60 μT, and points in the positive x direction. At t = 0 the electron has a velocity that has an x component of 30 km/s, a y component of 40 km/s, and a z component of zero. What is the radius of the resulting helical path?

• A) 4.7 mm
• B) 18 mm
• C) 3.8 mm
• D) 2.8 mm
• E) 5.7 mm

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Definitions:

Evolution

The evolutionary process that leads to the diversification and development of diverse living organisms from their predecessors throughout Earth's past.

Homology

A similarity in sequence or structure between different genes or proteins, often due to a common evolutionary origin.

Phylogeny

The evolutionary history and lineage of species or groups of species, construction of their "family tree".