问题
选择题
一台小型发电机产生的电动势随时间变化的正弦规律图象如图甲所示。已知发电机线圈内阻为5.0Ω，现外接一只电阻为95.0Ω的灯泡，如图乙所示。则
A.电压表V的示数为220 V
B.电路中的电流方向每秒钟改变50次
C.灯泡实际消耗的功率为484 W
D.发电机线圈内阻每秒钟产生的焦耳热为24. 2 J
答案
D
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一台小型发电机产生的电动势随时间变化的正弦规律图象如图甲所示。已知发电机线圈内阻为5.0Ω，现外接一只电阻为95.0Ω的灯泡，如图乙所示。则
A.电压表V的示数为220 V
B.电路中的电流方向每秒钟改变50次
C.灯泡实际消耗的功率为484 W
D.发电机线圈内阻每秒钟产生的焦耳热为24. 2 J
D
One sunny afternoon, a seven-year-old girl went for a walk. She crossed a large area of grassland into the woods __26__ she realized that she was lost. Sitting on a rock and __27__ what to do, she began crying. After a while. She__28__ to walk along a wide path lined with tall trees and thick bushes. __29__ it was getting dark, she saw a small, dark wooden house. She opened the door and __30__ stepped in. Suddenly, she heard a strange noise, and she ran out the door and back to the __31__. Cold and tired, she fell asleep near a __32__. The girl’s parents were out and her dog, Laddy, was at home. Laddy __33__ that his mistrees（女主人）was in danger. He jumped __34__ a window, breaking the glass. He looked in the fields. But he couldn’t find his mistress anywhere. However, from the ground came a __35__ scent (气味) as he lowered his head. He __36__ the scent and walked across the grassland. Barking __37__ into the air, the dog __38__ through the woods until he found the __39__ . But the girl was not there, so he headed back to the woods. Much to his __40__ , he saw his mistress’ blue shirt in the distance. He __41__ over some bushes and saw the little stream, where the girl was __42__. When she opened her eyes and 43 her dog standing beside her, the girl said, “you 44 me, Laddy,” and she kissed him several times. Seeing their daughter and dog coming back, the parents burst into tears of 45 . That night Laddy had a heror’s supper: a huge meal of steak
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