Yahoo奇摩 網頁搜尋

  1. First of all, after 20 minutes, the car has travelled 60 x (20/60) = 20 km. So at that time the car still has to travel 40km. If the car travels at 80 km/h for the remaining distance, it needs a further 40/80 = 0.5 hours or 30...

  2. Initial velocity, u = 50 km/h = 50 / 3.6 = 13.89 m/s Final velocity, v = 0 Stopping distance, s = 15 m By equation of motion, v2 = u2 - 2as 0 = (13.89)2 - 2a(15) Deceleration, a = 6.43 ms-2 Now, initial velocity, u = 70 km/h = 70/3.6 = 19.44 m/s By equation of motion, v2 = u2...

  3. Yes, the title of Executive is usually more senior than that of Administrator. I assume you are referring to an office in the private sector. An Executive is empowered to act (or execute) on behalf of the...

  4. (a) Distance covered by satellite in one revolution round the earth = 2 x pi x (350+6370) km where pi = 3.14159..... Hence, average speed = distance/time = 2 x pi x (350+6370) /1.5 km/h (b) Similar, distance covered by satellite in one revolution = 2 x pi x (h+ 6370) km where h (in km) is the...

  5. Time needed for reaching the MAXIMUM velocity : u=0, v=10ms^-1, a=3.3ms^-2, By v=u+at,10=0+3.3t t=10/3.3 s distance of the runner's velocity change from 0 to 10ms^-1 : By v^2-u^2=2aS, 10^2-0=2(3.3)S S=100/6...

  6. 當有一大串形容詞放埋一齊時,習慣上係有固定次序o既,點解要咁就真係考起,但你要講英文,就只能夠跟從呢個習慣。 根據 Michael Swan 著,Practical English Usage (p11, Oxford 2005),次序為: Size > Age >...

    分類:社會及文化 > 語言 2007年08月25日

  7. A man standing in a stationary lift releases a stone. The stone takes t seconds to reach the floor of the lift. If the lift is moving downwards with constant velocity instead of being stationary A.The stone...

  8. A car travels from town A to town B. It first moves at a speed of 60km/h for 20 minutes and then at 80km/h for the rest of time. What is the car’s average speed if the distance between town A and town B is 60km...

  9. friction compensated = 冇 friction 呢個net force. 因為如果你係平面推架車仔, 佢會有個friction 阻住你, 令你冇咁易推(net force 小左). or 你推完個friction 會整停佢. 但個斜路 佢係有個force 向下, 係mgsinx 咁當佢呢個mgsinx 同個木版gei friction 一樣, 咁佢就冇net force , 咁就好似冇左 令佢減速gei...

  10. change 60km/h into ms-1 60 X 1000/3600 = 16.67 90 x 1000/3600 = 25 120 x 1000/3600 = 33.33 The quesiton ask for the average acceleration fo the sports car, therefore it is a = initial and final / time taken 33.33 - 16.67 / (5+7) = 1.39ms-2 therefore the ans is D