Dust on Bookshelves and Elsewhere in a House Is Made

question 32

Multiple Choice

Dust on bookshelves and elsewhere in a house is made mostly of

• A)dry mucous.
• B)white blood cells.
• C)dried sweat and uric acid crystals.
• D)dead skin cells.
• E)pulverized minerals and "dirt."

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Definitions:

Electro-Magnets

Magnets created by passing an electric current through a coil of wire surrounding a metal core.

Magnetic Pole Fields

Invisible regions around a magnet where magnetic forces are exerted, characterized by north and south poles.

Squirrel Cage

A type of rotor found in induction motors, characterized by its cylindrical shape with conductive bars running the length and connected by rings at both ends, resembling a squirrel cage.