M |
M+m |
1 |
2 |
1 |
2 |
v | 20 |
M(2M+m)
| ||
2μg(M+m)2 |
1 |
2 |
v | 20 |
1 |
2 |
M
| ||
2gL(M+m) |
L |
2 |
1 |
2 |
v | 20 |
1 |
2 |
M
| ||
gL(M+m) |
M
| ||
gL(M+m) |
M
| ||
2gL(M+m) |
M |
M+m |
M(2M+m)
| ||
2μg(M+m)2 |
M
| ||
gL(M+m) |
M
| ||
2gL(M+m) |
A.物体的动能减少了0.6mgs |
B.物体的重力势能增加了0.5mgs |
C.物体的机械能减少了0.4mgs |
D.物体克服摩擦力做功0.1mgs |
|
A.W+mgh1-mgh2 | B.mgh2-mgh1-W |
C.mgh1+mgh2-W | D.W+mgh2-mgh1 |
A.物体动能损失了
| B.物体动能损失了2mgh | ||
C.系统机械能损失了2mgh | D.系统机械能损失了
|
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