A Friction Force

question 114

Multiple Choice

A friction force

• A) is a contact force that acts parallel to the contact surfaces.
• B) is a normal force between contact surfaces.
• C) is a scalar quantity since it can act in any direction along a surface.
• D) does not depend on the nature of the surfaces.

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Definitions:

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The cellular process of building proteins from amino acids based on the instructions coded in DNA and mediated by RNA.

Microfilament

Cytoskeletal element composed of actin subunits; reinforces cell membranes; functions in movement and muscle contraction.

Muscle Contraction

The process by which muscle fibers produce force and tension through the sliding of actin and myosin filaments, powered by ATP.

Nuclear Envelope

The double membrane structure that surrounds the nucleus in eukaryotic cells, controlling the flow of substances in and out of the nucleus.