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> 一物块在水平拉力F的作用下，从静止开始沿水平面运动了时间t 1后撤去F，又经时间t 2停止，则物块在运动过程中所受摩擦力的大小为（　　） A． F(t1+t2) t1 B． Ft2 (t1+t2) C． Ft1 (t1+t2) D． F(t1+t2) t2

问题：

发布时间：2024-09-10

一物块在水平拉力F的作用下，从静止开始沿水平面运动了时间t ₁后撤去F，又经时间t ₂停止，则物块在运动过程中所受摩擦力的大小为（　　）

A．

F(t1+t2)

t1

B．

Ft2

(t1+t2)

C．

Ft1

(t1+t2)

D．

F(t1+t2)

t2

参考答案：

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一物块在水平拉力F的作用下，从静止开始沿水平面运动了时间t 1后撤去F，又经时间t 2停止，则物块在运动过程中所受摩擦力的大小为（ ） A． F(t1+t2) t1 B． Ft2 (t1+t2) C． Ft1 (t1+t2) D． F(t1+t2) t2

可能感兴趣的题目：

一物块在水平拉力F的作用下，从静止开始沿水平面运动了时间t ₁后撤去F，又经时间t ₂停止，则物块在运动过程中所受摩擦力的大小为（　　）

A．

F(t1+t2)

t1

B．

Ft2

(t1+t2)

C．

Ft1

(t1+t2)

D．

F(t1+t2)

t2