ya 發問時間: 社會與文化語言 · 1 0 年前

有幾題Physics 的問題想請教~

1.

Which of the following is not likely a possible source of danger: an area with high electric

a. resistance

b. voltage

c. field

d. current

答C錯了

2.

A beam of light emerges from water into air at an angle. The beam is bent

a. toward the normal

b. away from the normal

c. will not bent at all

答C錯了

3.When we turn on a switch, the light bulb will be on immediately. This tells us ________.

a. the speed of free electrons in the circuit is very fast

b. the speed of free electrons in the circuit is as fast as the speed of light

c. the electric energy is very powerful

d. the electric field travels at speed of light

答B錯了

請問有人會解答嗎??我快被搞瘋了呀

麻煩大家幫幫忙

感激不盡!

謝謝

2 個解答

評分
  • ?
    Lv 7
    1 0 年前
    最佳解答

    1.(下面那一處較沒危險?有高電a.阻,b.壓,c.場,d.流的地方?

    Which of the following is not likely a possible source of danger: an area with high electric

    a. resistance

    b. voltage

    c. field

    d. current

    答案a.

    2. 光由水中以一斜角出射,進入空氣,則光a.偏向,b.偏離法線,c.不偏離法線.

    A beam of light emerges from water into air at an angle. The beam is bent

    a. toward the normal

    b. away from the normal

    c. will not bent at all

    答案b.根據Snell定律n1sinq1=n2sinq2,水的折射率n1>空氣的折射率n2,故出射角q2>入射角q1

    3.When we turn on a switch, the light bulb will be on immediately. This tells us ________. 開關一開燈就亮是因為在導線裡a.自由電子速度快,b.自由電子跟光速一樣快,c.電能很有力,d.電場以光速傳播.

    a. the speed of free electrons in the circuit is very fast

    b. the speed of free electrons in the circuit is as fast as the speed of light

    c. the electric energy is very powerful

    d. the electric field travels at speed of light

    答案是d. 電子在導線裡移動的速度很慢,但是能量的傳播跟光速一樣快.

  • 1 0 年前

    1. Which of the following is not likely a possible source of danger: an area with high electric

    問題問的是哪一個不危險,所以我想答案應該是 a. resistance

    a. electric resistance 電阻

    b. electric voltage 電壓

    c. electric field 電場

    d. electric current 電流

    2. A beam of light emerges from water into air at an angle. The beam is bent

    問題問的是若一束光線由水中射向空中則折射角度會....

    我想答案是 b. away from the normal

    (但我不太清楚他 normal 的定義....所以不太確定

    但總之會有一個偏折角度,可參考以下網站內圖片解說)

    http://www.phy.ntnu.edu.tw/demolab/optics/rainbow/...

    3. 3.When we turn on a switch, the light bulb will be on immediately. This tells us ________.

    問題說一切開關燈泡馬上亮,所以主要是在講電的傳導很快,跟光速以及電強不強應該沒有關係,

    所以選 a. the speed of free electrons in the circuit is very fast

    參考資料: me
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