问题 选择题
某同学将一直流电源的总功率P1、输出功率P2和电源内部的发热功率P3随电流I变化的图线画在了同一坐标上,如图中的a、b、c所示,根据图线可知(   )

A.反映P3变化的图线是b

B.电源电动势为8v

C.电源内阻为4Ω

D.当电流为0.5A时,外电路的电阻为6Ω

答案

答案:D

阅读理解

The people below are all trying to choose which TV programme to watch.  After the description of these people, there is information about six TV programmes A-F. Decide which programme would be most suitable for the person mentioned in questions 1-5 and then mark the correct letter (A-F) on your answer sheet. There is one extra paragraph about one programme which you do not need to use.

__________1.Although Rob lead a quiet life in a small village, that doesn’t stop him from wanting to find out about the latest scientific development.  

__________2.Bella enjoys eating out but can’t afford to spend very much at the moment as she is saving for a holiday. She has never learnt how to cook, so now might be quite a good time to find out!

____________3. Dan is interested in taking wildlife photographs and enjoys the kind of programme which gives him a chance to see a professional photographer at work.

_____________4. Gina is a music teacher. Although she prefers  classical music, she likes to follow the kind of music that interests the teenagers she teaches.

____________5.Ron’s wife is in hospital. He wants to finds a programme suitable for his three-year-old son while he gets on with the housework and prepares a meal.

TODAYS  TELEVISION  PROGRAMME  PREVIEW

A.TV1 7:20 p.m. Find out more about Australia’s animal life. This film was made last year by one of Australia’s best-known cameramen, Dougie Bond. He spent over 200 hours filming the birds, animals and fish that inhabit this beautiful continent and for the first time brings some of these unusual animals to our TV screens.

B.TV3 9:00p.m. The popular science programme is back with the latest in technology and medicine. This week, cars that run on sunlight and the story of one baby’s fight to live.

C.TV2 8:10p.m. Do you think what goes into the food most of us eat every day of the week? Tonight’s programme takes a serious scientific look at the bread industry. Whether you bake your own bread or just enjoy buying it, this programme will give you an interesting insight into something most of us eat every day of the week.

D.TV1 5:15p.m. Busy parents? Bored children? Do you want something educational to entertain your children while you do something else? This popular magazine programme is for the under-fives. More music, fun, songs and games with Carla and Larry.E.TV3  8:45p.m. If you’ve always wanted to cook, now’s your chance to learn. In the studio are two chefs who will take you through some simple recipes step by step. This is a repeat of the popular series shown last year, and available from good bookshops.

F.TV3   7:40p.m. The latest new music. Pete Hogg looks at the best of the current rap, raga and new jack swing plus new video releases. This is the programme that tells you all about what’s happening on the music scene and brings you interviews with tomorrow’s young artists.

单项选择题