Is it true that if everybody in China jumped then the Earth would have an impact and move slightly? If so why?

Question: Is it true that if everybody in China jumped then the Earth would have an impact and move slightly? If so why?
- Keywords:
  china,
  phyiscs,
  quirky
Asked by Anna :D to Stefan, Anna on 12 Nov 2014.
- Stefan Lines answered on 12 Nov 2014:
  
  Even if one person jumped, such as yourself, the force from you pushing on the Earth would move it the smallest amount – but then mid jump, gravity would kick in, with you and the Earth being attracted to each other, and the earth (and you) would move back to exactly the same position 🙂
  
  Simply… it is not possible to move the planet off its orbit by jumping. (Probably a good thing!)

Question: Is it true that if everybody in China jumped then the Earth would have an impact and move slightly? If so why?