Hai hòn đá được thả rơi vào trong cái hố, hòn đá thứ 2 thả vào sau hòn đá đầu 2 giây.Bỏ qua sức cản không khí. Khi 2 hòn đá còn đang rơi , sự chênh lệch về vận tốc của chúng trong quá trình rơi là:

Chia sẻ

Một số câu hỏi khác có thể bạn quan tâm.

• Find a mistake in the four underlined parts of the sentence and correct it:

  You should eat less and do more exercises if you want to be overweight.

• Choose the word that has the underlined part pronounced differently from the rest: 

  site                           visually                          mine                            guide 

• Choose a word that has different stress pattern:

  possessive                expensive                   talkative                  demonstrative

• Find a mistake in the four underlined parts of the sentence and correct it:

  We cannot work out the reason of the problem.

• Choose the correct sentence which is built from the words and phrases given:

  My grandparent / house / end / road //.

• Choose the correct sentence which is built from the words and phrases given:

  Reach / grandparent / house / turn right / parking lot / left / the corner //.

• Choose one sentence that has the same meaning to the root one:

  He agreed to go climbing although he hated heights.
  
  

• Choose one sentence that has the same meaning to the root one:

  Unless you measure with the greatest accuracy, the door won’t fit and we’ll have trouble with it.
  
  

• Choose one sentence that has the same meaning to the root one:

  You should have more sense of responsibility when you age 18.
  
  

• Choose one sentence that has the same meaning to the root one:

  I have to hurry to he online before 9.00 this morning.