试题与答案

如图所示,滑轮重力和摩擦均不计,物体重均为100N,与水平面间的摩擦力都是30N

题型:选择题

题目:

如图所示,滑轮重力和摩擦均不计,物体重均为100N,与水平面间的摩擦力都是30N,作用于各绳端的拉力分别为F1、F2、F3.,要使物体做匀速直线运动,则下列说法中正确的是(  )

A.F1=100N、F2=50N、F3=200N

B.F1=30N、F2=60N、F3=15N

C.F1=100N、F2=50N、F3=50N

D.F1=30N、F2=15N、F3=60N

答案:

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参考答案:天冬氨酸;谷氨酸

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