U-shaped valleys

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Q1: A valley cut by a river is V-shaped. What does it turn into when a glacier flows into it?

[Answer]

Valleys that have been worn away by glaciers have a special shape. The valleys have wide, flat floors and very steep sides. We call them 'U-shaped valleys' because they look like the letter U when seen from the side.

When ice fills a valley it weighs down heavily on the valley floor. Stones trapped between the ice and the valley are pulled along by the ice, scraping the valley floor and making it flat and wide.