Question

Microwaves may be great at warming up food, but what about warming people?

Using microwaves to directly heat owners of a room would save much of the energy wasted by heating walls and furniture. And despite popular ideas about microwaves, this technique would be safe, according to Charles R. Burlier of the Microwave Research Center in Marlborough, New Hampshire. Low-power microwaves only penetrate (貫穿) the skin (low-power microwave penetration in a ham is about 0.2 inches, for example) and with no negative effects.

To test this idea, Buffler subjected himself to microwaves in a special room using a standard 500-watt, 2459 MHz magnetron (磁控管). He found that a person will start to feel warmth at about 20 milliwatts per square centimeter (mw. / sq. cm. ) ; a satisfactory feeling of warmth occurs between 35 and 50mw. / sq. cm. By comparison, a person standing in noonday summer sun feels the amount of 85 mw. / sq. cm. And a frozen meat pie in your microwave oven receives about 1000 mw. / sq. cm.

In houses of the future, each room could be provided with its own magnetron, says Buffler. When you stepped into the living room, for example, a motion detector (運動感應器)would turn on the magnetron, filling the room with low-power microwaves. In the same way that a microwave oven heats up a hamburger, but not the plate it’s on, you would feel warmth from the microwaves without changing the temperature of your coffee table. (You could, however, make your favorite easy chair even more comfortable by treating it with a radiation-absorbing chemical.)

While it might be some time before homeowners are comfortable enough with the idea to set up whole-body microwave heaters in houses, Buffler says microwaves may attract livestock(家畜) farmers. Lambs that are born outdoors in winter, for example, are frequently lost to cold. Microwaves could warm the lambs safely and quickly.

1.Which of the following can tell the main idea of the passage?

A．A new heating system.                   B．A new microwave oven.

C．A popular technique.                     D．The magnetron.

2.According to Paragraph 2, which of the following does not describe the characteristics of a microwave heater?

A．It directly heats people in a room.

B．It heats walls and furniture in a room.

C．It is safe.

D．It saves energy.

3.The test conducted by Buffler shows that when a person feels comfortable warmth, he receives about ________________.

A．20 mw. / sq. cm.    B．40 mw. / sq. cm.     C．60 mw. / sq. cm.     D．85 mw. / sq. cm.

4.According to Paragraph 4, which of the following fills the room with low-power microwaves?

A．The magnetron.                        B．The motion detector.

C．The microwave oven.                    D．The radiation-absorbing chemical.

5.Which of the following statements about microwave heaters would Buffler most probably agree with?

A．Microwave heaters will soon be widely used by homeowners.

B．Microwave heaters sometimes make people feel uncomfortable.

C．Perhaps microwave heaters will be first used by livestock farmers, who wish to protect their lambs in winter.

D．Microwave heaters cannot be accepted by the public because they are somewhat unsafe.

 

Answer 1

【答案】

1.A

2.B

3.B

4.A

5.C

【解析】

試題分析：本文是一篇說明文，談及微波爐可以使人暖和，人們不必浪費能量給墻壁和家具加熱。微波直接進入人的皮膚使人溫暖，既安全又省能源。在未來，微波爐也許還有其它的用途。

1.細節理解題。根據文章第二自然段說明微波爐可以使人暖和，不必浪費能量給墻壁和家具加熱。故選A。

2.細節理解題。根據文章第二自然段說明微波直接進入人的皮膚使人溫暖，既安全又省能源。故選B。

3.細節理解題。根據從“a satisfactory feeling of warmth occurs between 35 and 50mw./sq. cm.”可知。故選B。

4.細節理解題。根據從第四自然段 a motion detector would turn on the magnetron…可知答案為A。

5.主旨大意題。根據最后一自然段暗示了答案。也許微波加熱器將首先將被飼養牲畜的農民使用,他們希望在冬季保護他們的羊羔。故選C。

考點：日常生活類短文閱讀。

點評：主旨大意題，就是指那些針對文章的主要內容、主題、標題或寫作目的所設置的問題。這類題主要考查同學們在理解全文的基礎上運用概括、判斷、歸納、推理等邏輯思維方法對文章進行高度概括或總結的能力。要尋找這類文章的主旨大意就需要研究文章的主題句。