题干

人类社会前进的每一步都和能源有利用息息相关.

(1)下列能源:①煤、②石油、③天燃气、④水能、⑤风能、⑥核能、⑦太阳能、⑧潮汐能中,属于可再生能源能源的是____ (只填序号)

(2)微波炉已进入千家万户,微波炉使用的能源是____ (选填“一次”或“二次”)能源;一只铭牌如图所示的微波炉将500g的牛奶[比热容c=4.2×103J/(㎏•℃)]从10℃加热到60℃时,用时2.5min,此过程牛奶吸收的热量是____ J,消耗的电能是____ J.

(3)核能发电的优点是只需消耗很少的核燃料就可以产生大量的电能.1㎏铀235的核全部裂变释放的能量约等于2.5×106㎏标准煤(热值q=3×107J/㎏)完全燃烧放出的热量.若南京市的一年用电量约为3×1010kW•h,则只需____ ㎏的铀235用于发电即可;但科学技术的发展往往是一把双刃剑,“3•11”日本超级大地震引发的核电站爆炸,造成了大面积的核污染,给人们留下了深重的灾难!所以核电站必须采取多种可靠的防护措施.同学们,看到图示的警示符一定要远离!

上一题 下一题 0.0难度 选择题 更新时间:2018-03-02 03:01:41

答案(点此获取答案解析)

④⑤⑦⑧,二次,105000,165000,1440

同类题3

完形填空

    Emily was an eighth grader. To pass her Civics course, she had to do some volunteer services in a nursing home for a week.

    One Monday, Emily went to the nursing home after school. When she arrived, she was told she would spend an hour every weekday with an elderly lady, Mrs Blair. She was then led into a room, where an old lady in a flowery dress was sitting on a sofa.

    Emily stood awkwardly(别扭地)in front of the lady. She cleared her throat and said, "Good afternoon. I'm Emily."

    "Good afternoon, Emily. Take a seat, please." Mrs. Blair replied.

    Then,1filled the space between them. Emily wondered what to say.

    "Tell me about yourself, Emily," Mrs Blair said suddenly.

    "Well," Emily started, "I don't have any grandparents, so I don't know how to get on well with elderly people. I love the performing arts. I'm here mainly because I have to volunteer here to get a good grade for my Civics class."

    Mrs Blair didn't seem to mind. 'Many people, especially teens, don't seem to2old people like me. Now you are here, and I'm going to change that about you. Ask me anything."

    Emily thought for a moment, and finally decided, "What was your job?"

    "I was a Broadway star in the 1950s."MrsBlair answered.

    Cool! Can you tell me about it?" Emily asked, amazed.

    Mrs Blair smiled. "Back then3the lead actress had the honor to wear a special bracelet. I was the lead in almost all of the plays, so I always wore the bracelet. Till this day, I still have it."

    Emily smiled along with Mrs Blair and listened to the other stories attentively. She had become very4Mrs Blair's stories. She decided to come earlier the next day.

    Tuesday, Wednesday, and Thursday passed by quickly. Then came Friday. As she was leaving, Emily was really upset to say goodbye.

    "Don't be sad. You can still visit me," Mrs Blair comforted her. She then handed a small box to Emily, "It's my gift to you."

    Emily5opened the box and was surprised to see what was inside. "It's the bracelet that you wore. Thank you!" Emily said, with tears in her eyes free.

    I'm sure to visit you whenever I'm on the way home, Emily thought of her own love for the performing arts. She touched the bracelet and6that she would keep her word to Mrs Blair.