ʱ : ڶ 九年级物理??练”:18.2.1 电功?课前预习+随堂练习+达标练习,含答? - 百度文库ϿʼĶ
ڶ 繦
1ʱ
ǰԤϰ
1. 繦DZʾ 2. 繦ʡݶ壺P = W = UIt21ͽȨ
ԣP = W/t = = ʽ繦ʵ ij˻www-2-1-cnjy-com
3. 繦ʵλ
1 kW= W 1W= mW 4. ͼΪijݵƣݣ
˵ݵĶѹΪ Ϊ
жѹUʾ жʣPʾ 5. õֵͲøɵԴʱΪO32AС
ݵĵ繦ʽӽ ( )
A1W B10W C0.1KW D1KW ϰ
1.˵ȷ Aǧߡʱǵ繦ʵĵλǧǵ繦ĵλ BܱDzõʵDZ Cʴõĵĵһ
DΪ100ߵõ10Сʱĵ1ǧʱ 2. ڵ繦ʣ˵ȷ A繦DZʾ B繦DZʾٵ
Cõĵ繦Խĵ繦һ Dʵʹʲܴڶ
3. мסҡյƣֱС220V 40W110V 40W36V 40WǾڶѹ¹Ƚǵȣһյ. www.21-cn-jy.com
A. B. C. D.һ
4. ڶѹͶʣ˵ȷ AõʱʵʹǵĶ Bõʱ˵ĵѹǵĶѹ
Cõ˵ʵʵѹѹʱʵʹСڶ
Dõ˵ʵʵѹСѹʱʵʹСڶ
5. ʹһС12V 6WСڵѹΪ18VĵԴ⣬ һ ĵRʱRĹΪ W21cnjy.com ϰ
6.λѧУ繦ʵλ