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在力的作用下如果能繞著一固定點轉動的硬棒就叫杠杆.在生活中根據需要,杠杆可以做成直的,也可以做成彎的.定滑輪是一種等臂杠杆,動滑輪是一種動力臂是阻力臂的兩倍的杠杆杠杆平衡的條件:動力×動力臂=阻力×阻力臂或…
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