题目

关于电路中感应电动势的大小，下列说法中正确的是：（     ） A.穿过电路的磁通量越大，感应电动势就越大 B.电路中磁通量的该变量越大，感应电动势就越大 C.电路中磁通量变化越快，感应电动势越大 D.若电路中某时刻磁通量为零，则该时刻感应电流一定为零 答案：C　　Clark and Luice like sports very much. In summer they swim and in winter they skate. They are going skating this weekend, but they don't know how the weather will（将会）be. It's 7∶35 now, and they are watching TV. They are listening to the weather report（预报）for the weekend: Friday is going to be cold and cloudy, but it isn't going to rain. The temperature（温度）is going to be below（低于）zero. It's going to snow on Friday evening. Saturday and Sunday will be cold and sunny. 　　Now, Clark and Luice are very happy. They think they will have a good time then. (1) Clark and Luice like ________ very much. [　　] A．listening to the weather report B．watching TV C．playing D．sports (2)They are going ________ this Saturday and Sunday. [　　] A．swimming in the river B．skating C．have a party in the classroom D．to skating (3) They want to know about ________. [　　] A．the rain B．the food C．the weather D．the radio (4) It ________ this weekend. [　　] A．will rain heavily B．will be snowy C．will be hot and cloudy D．will be cold and sunny (5) They are happy after they listen to the weather report, because ________. [　　] A．they want to see their good friend B．they are going to have a picnic on the hill C．they are going to have a football match in the open air D．the weather will be fine and they can go skating