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          按照?qǐng)D的要求畫出滑輪組的繞繩方法(不計(jì)滑輪重、繩重及摩擦)
          			
          


			
          

		
          
		
		
	
          
		
          
			
          
				
          
				

          試題分析：動(dòng)滑輪被幾根繩子承擔(dān)，拉力就是物體和動(dòng)滑輪總重的幾分之一（1）F=，由4段繩子承擔(dān)滑輪的重；（2）F=，由5段繩子承擔(dān)滑輪的重．

          點(diǎn)評(píng)：滑輪組設(shè)計(jì)原則可歸納為：奇動(dòng)偶定；一動(dòng)配一定，偶數(shù)減一定，變向加一定．
          				
          
							
          
			
          
			
          
			
			
          
		
          
	
          

		
          

		





			
          
		
          
		
				
          
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