Trên hành tinh X , gia tốc rơi tự do chỉ bằng  gia tốc rơi tự do trên trái đất. Vậy nếu thả vật rơi từ độ cao h trên trái đất mất thơi gian là t thì cũng ở độ cao đó vật sẽ rơi trên hành tinh X mất bao lâu?

Chia sẻ

Một số câu hỏi khác có thể bạn quan tâm.

• Choose the best answer for the following sentence:

  Most parents have total confidence ___________  the school.

   

• Choose the best answer for the following sentence:

   Friends make us ___________ more comfortable and cheerful in life.

   

• Choose the best answer for the following sentence:

  ''If you are late again, I will sack you,'' the boss ___________ him.

   

• Choose the best answer for the following sentence:

  John said that at 9 o’clock the day before he ____________ the monthly report.

   

• Choose the best answer for the following sentence:

  He offered ______________ these bags.

   

• Choose the best answer for the following sentence:

  John ______________ for London three years ago.

   

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

  She invited us to her birthday party last week.
  
  

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

  I cannot play any sports and I cannot play any musical instruments, either.
  
  

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

  Tomorrow we will go to the zoo or we will visit the citadel because we don’t have much time.
  
  

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

  Mr. Green is my teacher and he is my great friend, too.