Pulley



GRE

解释

GRE 红宝书

• n.滑轮, 滑车
• ［英］ n.滑轮, 滑车 ( a wheel used to transmit power by means of a band, belt, cord, rope, or chain passing over its rim[轮缘])
• ［记］ pull ( 拉) ＋ey

Webster Collegiate

noun (plural pulleys)

• Etymology: Middle English poley, pully, from Anglo-French pulie, probably ultimately from Greek polos axis, pole — more at pole
• Date: 14th century
• 1. a sheave or small wheel with a grooved rim and with or without the block in which it runs used singly with a rope or chain to change the direction and point of application of a pulling force and in various combinations to increase the applied force especially for lifting weights
• 2. a pulley or pulleys with ropes to form a tackle that constitutes one of the simple machines
• 3. a wheel used to transmit power by means of a band, belt, cord, rope, or chain passing over its rim

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