1 |
2 |
1 |
2 |
x | 21 |
1 |
2 |
v | 20 |
FT | ||
|
1 |
2 |
x | 21 |
1 |
2 |
v | 21 |
1 |
2 |
v | 20 |
1 |
2 |
x | 22 |
1 |
2 |
v | 22 |
1 |
2 |
x | 21 |
1 |
2 |
v | 21 |
1 |
M |
|
1 |
2 |
1 |
2 |
x | 21 |
1 |
2 |
v | 21 |
| ||
k
|
v | 20 |
| ||
k
|
FT | ||
|
1 |
M |
|
| ||
k
|
A.8m/s | B.10m/s | C.15m/s | D.20m/s |
A.物块的机械能逐渐增加 | ||
B.软绳重力势能共减少了
| ||
C.物块重力势能的减少等于软绳克服摩擦力所做的功 | ||
D.软绳重力势能的减少小于其动能的增加与克服摩擦力所做功的和 |
πR |
2 |
2v0 |
3 |
© 2017-2019 超级试练试题库,All Rights Reserved.