The Margins of Glaciers Are Usually Darker Than the Interior

question 92

Multiple Choice

The margins of glaciers are usually darker than the interior primarily because:

• A) shearing causes the ice to expel air and become darker
• B) glaciers are transparent so the underlying bedrock is visible
• C) the sides are moving faster than the interior of the glacier
• D) the sides have a higher concentration of rocks and other debris
• E) all of these

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Definitions:

Clamping Force

The force applied to hold two or more objects together, preventing movement or separation.

Yield Point

The stress at which a material begins to deform plastically, after which deformation will occur without any increase in load.

Internal Threads

Threads located on the inside surface of a hole or cylinder, designed to mate with external threads of a bolt or screw.

Tap

A hand- or machine-actuated tool used to cut internal threads.