挑战习题
1/5单选题
难度:

1.

如图所示,杠杆在水平位置处于平衡状态,杠杆上每格均匀等距,每个都相同. 下列四项操作中,会使杠杆右端下倾的是(  )
①将杠杆两侧的钩码同时各向外移动一小格
②将杠杆两侧的钩码同时各向内移动一小格
③在杠杆的两侧同时各减掉一个钩码
④在杠杆的两侧钩码下同时各加挂一个相同的钩码.


A

②③

B

②④

C

①③

D

①④

提示1:
PHA+5bem5Y+z6YeN5Yqb5q+U5pivMjoz77yM5Yqb6IeC5q+U5bqU6K+l5pivMzoy77yM6KaB5oOz6YeN5paw5bmz6KGh77yM56e75Yqo5Yqb6IeC6ZW/55+t5Lmf5bqU6K+l5pivMzoyPC9wPg==
提示2:
PHA+5oiW6ICF5ZCM5pe25Lik56uv6YeN5Yqb5YeP5bCR77yI5oiW5aKe5Yqg77yJ5LmL5q+U5Lmf5pivMzoy5omN6IO96L6+5Yiw5bmz6KGh44CCPC9wPg==
提示3:
PHA+5Y+z5L6n5LiL6ZmN77yM5bqU6K+l5piv5Y+z5L6n56Cd56CB6YeN6YeP5LmY5Lul5qC85pWw5aSn5LqO5bem5L6n56Cd56CB6YeN6YeP5LmY5Lul5qC85pWwPC9wPg==
正确答案:Qw==
PGRpdj7mnaDmnYblubPooaHlkI7vvIzmlLnlj5jlipvoh4LmiJbogIXliqjlipvlkozpmLvlipvvvIzlpoLmnpzmg7Pnu6fnu63ovr7liLDlubPooaHvvIzmnaDmnYbplb/nn63lop7liqDnmoTmr5TkvovlupTor6XmmK/liqjlipvoh4LlkozpmLvlipvoh4LnmoTmr5TlgLzvvIzlkIzmoLflpoLmnpzlop7liqDmiJblh4/lsJHliqjpmLvlipvnmoTor53vvIzlop7liqDmiJblh4/lsJHnmoTmr5Tkvovov5jlupTor6XmmK/liqjpmLvlipvkuYvmr5TvvIzmiY3og73lho3mrKHlubPooaHjgII8L2Rpdj4=