问题
填空题
照明白炽灯的灯丝断了一截，把两段灯丝搭接上后仍能使用，则搭接后灯丝的电阻将变______；接在电路中，灯泡的亮度将变______．
答案
由题意灯丝断了一截，然后又搭接上可知：L变小，s变大，由公式R=ρ
可得电阻变小；L s
由题意可知灯泡两端电压不变，灯泡电阻变小，由公式P=
可得灯泡电功率变大．U2 R
故答案为：小；亮
搜题请搜索小程序“爱下问搜题”
照明白炽灯的灯丝断了一截，把两段灯丝搭接上后仍能使用，则搭接后灯丝的电阻将变______；接在电路中，灯泡的亮度将变______．
由题意灯丝断了一截，然后又搭接上可知：L变小，s变大，由公式R=ρ
可得电阻变小；L s
由题意可知灯泡两端电压不变，灯泡电阻变小，由公式P=
可得灯泡电功率变大．U2 R
故答案为：小；亮
| 阅读理解。 | |||||
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| A. 3338651 B. 8947659 C. 7026449 D. 9796788 | |||||
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| A. at 8:00 a.m. on Saturday morning B. at 2 p.m. on October 5th C. at 6:30 a.m. on Monday D. on Sunday morning | |||||
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| A. A 23-year-old young man. B. A 28-year-old single man. C. A 50-year-old single lady. D. A 28-year-old married (已婚) woman. | |||||
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