1 |
2 |
v | 20 |
1 |
2 |
v | 21 |
1 |
2 |
v | 22 |
1 |
2 |
1 |
2 |
1 |
2 |
v | 20 |
1 |
2 |
1 |
2 |
| ||
2 |
mv′2 |
R |
3m
| ||
4R |
3m
| ||
4R |
1 |
2 |
1 |
2 |
3m
| ||
4R |
A.F1sinθ+F2cosθ=mg sinθ,F2≤mg |
B.F1cosθ+F2sinθ=mg sinθ,F2≤mg |
C.F1sinθ-F2cosθ=mg sinθ,F2≤mg |
D.F1cosθ-F2sinθ=mg sinθ,F2≤mg |
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