本课配套习题挑战模式1/5
假如没有摩擦,下列哪种现象不可能发生( )
A: 地面上滚动的球、行驶的车辆很难停下来 |
B: 手拿不住写字的笔 |
C: 人可以在地面上行走如飞 |
D: 用吹灰之力可以推动火车沿轨道运动 |
- 提示1:PHA+5Lq66LWw6Lev5piv5L6d6Z2g6Z6L5bqV5LiO5Zyw6Z2i6Ze055qE5pGp5pOm77yM5b2T5pGp5pOm5Yqb5raI5aSx5ZCO77yM5Lq65bCG5peg5rOV6KGM6LWwPC9wPg==
- 答案:Qw==
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
本课配套习题挑战模式2/5
关于滑动摩擦力下面哪种说法是正确的()
A: 摩擦力随物体重力增加而增大 |
B: 在接触面粗糙程度相同时,摩擦力随压力增大而增大 |
C: 摩擦力只与接触面的粗糙程度有关 |
D: 摩擦力的大小总是不变的 |
- 提示1:PHA+5Zyo5o6l6Kem6Z2i57KX57OZ56iL5bqm55u45ZCM5pe277yM5omA5Y+X5Y6L5Yqb6LaK5aSn77yM5ruR5Yqo5pGp5pOm5Yqb6LaK5aSnPC9wPg==
- 答案:Qg==
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
本课配套习题挑战模式3/5
人在一般情况下步行前进时,若鞋底与地面不打滑,下列说法中正确的是( )
A: 地面对鞋底的摩擦力方向向后,阻碍人前进 |
B: 地面对鞋底的摩擦力方向向前,推动人前进 |
C: 鞋底花纹磨损后,摩擦力减小,人更容易前进 |
D: 鞋底花纹磨损后,摩擦力增大,人更难前进 |
- 提示1:PHA+5Lq65LmL5omA5Lul6LWw6Lev5pe25ZCR5YmN77yM5piv5Zug5Li65Zyw6Z2i57uZ5Lq66Z6L5bqV55qE5pGp5pOm5Yqb5ZCR5YmNPC9wPg==
- 答案:Qg==
PHA+5Lq65LmL5omA5Lul6LWw6Lev5pe25ZCR5YmN77yM5piv5Zug5Li65Zyw6Z2i57uZ5Lq66Z6L5bqV55qE5pGp5pOm5Yqb5ZCR5YmN77yM5omA5LulQemUmeivr+OAgULmraPnoa7vvJs8YnI+6Z6L5bqV6Iqx57q556Oo5o2f5ZCO77yM6Z6L5LiO5Zyw6Z2i55qE5o6l6Kem6Z2i55qE57KX57OZ56iL5bqm5YeP5bCP77yM5pGp5pOm5Yqb5YeP5bCP77yM5Lq65pu06Zq+5YmN6L+b77yM5omA5LulQ+ivtOS6uuabtOWuueaYk+WJjei/m+aYr+mUmeivr+eahO+8jETor7Tmkanmk6blipvlop7lpKfkuZ/mmK/plJnor6/nmoTvvJs8YnI+5pWF6YCJQu+8jjwvcD4=
本课配套习题挑战模式4/5
下列日常事例中,属于增大摩擦的是
A: 拉杆旅行箱底部装有轮子 |
B: 鞋底刻有凹凸不平的花纹 |
C: 向自行车的转轴处加润滑油 |
D: 在气垫船底和水之间形成一层空气垫 |
- 提示1:PHA+5peF6KGM566x5bqV6YOo6KOF5pyJ6L2u5a2Q77yM5bCG5ruR5Yqo5pGp5pOm5Y+Y5Li65rua5Yqo5pGp5pOm77yM5YeP5bCP5pGp5pOm5YqbPC9wPg==
- 提示2:PHA+5ZCR6Ieq6KGM6L2m55qE6L2s6L205aSE5Yqg5ram5ruR5rK577yM5YeP5bCP5pGp5pOm5YqbPC9wPg==
- 提示3:PHA+5rCU5Z6r6Ii55bqV5ZKM5rC05LmL6Ze05b2i5oiQ5LiA5bGC56m65rCU5Z6r77yM5YeP5bCP5pGp5pOm5YqbPC9wPg==
- 答案:Qg==
PHA+6Z6L5bqV5Yi75pyJ5Ye55Ye45LiN5bmz55qE6Iqx57q577yM5pS55Y+Y57KX57OZ56iL5bqm5aKe5aSn5pGp5pOm5Yqb44CB5omA5Lul6YCJQjwvcD4=
本课配套习题挑战模式5/5
如图所示,物体被夹在竖直且平行的木板之间,若将物体A竖直向上抽出去,则物体受到的摩擦力的方向是
A: 竖直向下 |
B: 竖直向上 |
C: 水平向左 |
D: 水平向右 |
- 提示1:PHA+5Yik5pat5pGp5pOm5Yqb55qE5pa55ZCR77yM6ZyA6KaB5Yik5pat54mp5L2T55qE6L+Q5Yqo5pa55ZCR5oiW6ICF6L+Q5Yqo6LaL5Yq/PC9wPg==
- 答案:QQ==
PHA+54mp5L2T5ZCR5LiK6L+Q5Yqo77yM5pGp5pOm5Yqb5pa55ZCR5ZCR5LiL44CC5omA5Lul6YCJQTxicj48L3A+