Bowlder

例句:

• This is exactly the amount of work which would have been necessary to raise the bowlder directly. 伯莎M.克拉克. 科学通论.
• By means of a lever, a 600-pound bowlder can be easily pried out of the ground. 伯莎M.克拉克. 科学通论.
• The problem of the builder is to get the heavy bowlder out of the ground, to load it on a wagon for transportation, and finally to raise it to the tower. 伯莎M.克拉克. 科学通论.
• The man pushes down with a force of 100 pounds, but with that amount succeeds in prying up the 600-pound bowlder. 伯莎M.克拉克. 科学通论.
• He finds it easier to exert a force of 100 pounds continuously until his end has moved 3 feet rather than to exert a force of 600 pounds on the bowlder and move it 6 inches. 伯莎M.克拉克. 科学通论.
• Suppose a 600-pound bowlder which is embedded in the ground is needed for the tower of a building. 伯莎M.克拉克. 科学通论.
• A man wishes to load the 600-pound bowlder on a wagon, and proceeds to do it by means of a plank, as in Figure 93. 伯莎M.克拉克. 科学通论.
• The man must lower his end of the lever 3 feet in order to raise the bowlder 6 inches out of the ground. 伯莎M.克拉克. 科学通论.
• By the use of an inclined plank a strong man can load the 600-pound bowlder on a wagon. 伯莎M.克拉克. 科学通论.

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