题干

某发电厂原来用11kV的交流电压输电,后来改用升压变压器,将电压升高到220kW输电,输送的电功率都是P,若输电线路的电阻为R,则下列说法中正确的是(    )

A:根据公式I=UR,提高电压后输电线上的电流增为原来的20倍

B:根据公式P=U2R,提高电压后输电线上的功率损耗将增大为原来的400倍

C:根据公式P=I2R,提高电压后输电线上的功率损耗减小为原来的1400

D:根据公式P=UI,提高电压后输电线上的功率损耗增大库原来的20倍

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C

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    Welcome to the Painting Competition for Woolands Students.

The International Anti﹣Drug Day this year is coming soon. In order to raise teenagers awareness to fight against drug taking. The seat on the council is going to hold a painting competition for the students in our city.

    Students who want to take part in the competition can hand in their own 2D paintings in either of the following two ways:

Each school will be provided with a box for students to put in their paintings. Boxes will be picked up by the City Art Council on Thursday, July 23rd, 2016, before the end of the school day.

    Paintings can be also handed in on Friday, July 24th, from 8: 00am to 10: 00am at the Woodlands Art Hall.

    Or paintings are required to be, 60cm wide by, 80cm long, or smaller. Larger sizes of you not be accept. Each student can only hand in one painting.

The final decision on the competition results will be made on June 26th, the Anti﹣Drug Day. The name list of the winners will be made known on the website of the City Art Council on the same day. All women paintings will be shown to the public at the City Youth Park from June 27th till the end of July.

Prize: 1st Prize(10students)=﹩300GiftCardeach.

2ndPrize(20students)=﹩200Gift Card each.

3rd Prize(30students)=﹩100Gift Card each.

For further information: Visithttp://www. woodlandsartcouncil. org. cn

call 2569﹣8632.