A.正常发光 | B.比正常发光暗 |
C.比正常发光亮 | D.无法判断 |
P1 |
U1 |
20W |
12V |
5 |
3 |
P2 |
U2 |
5W |
3V |
5 |
3 |
5 |
3 |
5 |
3 |
A.大于10W | B.等于10W | C.小于10W | D.不能确定 |
A.100W | B.25W | C.50W | D.20W |
A.P1=2P2 | B.P2=2P1 | C.P2=4P1 | D.P1=4P2 |
A.P2变小,P变小 | B.P2不变,P变小 |
C.P1变小,P2变大 | D.P1变大,P2变小 |
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