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1.用轻绳连接并跨过定滑轮(不计滑轮的质量和摩擦),悬于空中,放在斜面上,均处于静止状态. 当用水平向左的恒力推时,仍静止不动,则(  )
A:受到的摩擦力一定变小
B:受到的摩擦力一定变大
C: 轻绳上的拉力一定变小
D: 轻绳上的拉力一定不变
  • 提示1IOeJqeS9kzxpbWcgd2lkdGg9MTYgaGVpZ2h0PTE3IHNyYz0iaHR0cHM6Ly9wMi5xaW5nZ3VvLmNvbS9HMS9NMDAvOTcvQkIvckJBQ0UxT1RNb3J3U195c0FBQUJJbldMNkxzOTMxLnBuZyI+5aeL57uI5aSE5LqO6Z2Z5q2i54q25oCB77yM5YiZ57uz5LiK55qE5ouJ5Yqb5oGS562J5LqO54mp5L2TPGltZyB3aWR0aD0xNiBoZWlnaHQ9MTcgc3JjPSJodHRwczovL3AyLnFpbmdndW8uY29tL0cxL00wMC85Ny9CQi9yQkFDRTFPVE1vcndTX3lzQUFBQkluV0w2THM5MzEucG5nIj7nmoTph43lipvvvIzkuI3kvJrlj5HnlJ/lj5jljJY=
  • 提示2IOacquWKoDxpbWcgd2lkdGg9MTcgaGVpZ2h0PTE3IHNyYz0iaHR0cHM6Ly9wMi5xaW5nZ3VvLmNvbS9HMS9NMDAvNUIvQUYvckJBQ0ZGT1RNb3J3MVNLRUFBQUJMaTRtNWhFNzMyLnBuZyI+5pe277yM54mp5L2TPGltZyB3aWR0aD0xNiBoZWlnaHQ9MjEgc3JjPSJodHRwczovL3AxLnFpbmdndW8uY29tL0cxL00wMC85Ny9CQi9yQkFDRTFPVE1vcnhtekViQUFBQlZTVmh6TzA0NzUucG5nIj7lpITkuo7pnZnmraLnirbmgIHvvIw8aW1nIHdpZHRoPTE2IGhlaWdodD0yMSBzcmM9Imh0dHBzOi8vcDEucWluZ2d1by5jb20vRzEvTTAwLzk3L0JCL3JCQUNFMU9UTW9yeG16RWJBQUFCVlNWaHpPMDQ3NS5wbmciPuaJgOWPl+mdmeaRqeaTpuWKm+aWueWQkeS4jeehruWumi4=