A 20-Cm Length of Wire Centered on the Origin Carries a a 20-A

question 51

Multiple Choice

A 2.0-cm length of wire centered on the origin carries a 20-A current directed in the positive y direction. Determine the magnetic field at the point x = 5.0 m on the x-axis.

• A) 1.6 nT in the negative z direction
• B) 1.6 nT in the positive z direction
• C) 2.4 nT in the negative z direction
• D) None of the above

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Definitions:

T Tubules

Transverse tubules; system of inward extensions of the muscle fiber plasma membrane.

ATP

The energy necessary for metabolic processes in cells is transported by a molecule called adenosine triphosphate, or ATP.

Action Potential

An electrical signal resulting from depolarization of the plasma membrane in a neuron or muscle cell. Compare with resting potential.

Bone Mineral

Inorganic substances, primarily hydroxyapatite crystals, that give bones their hardness and strength.