There would probably be a huge earthquake.
If everyone on Earth jumped at the same time, the impact would be very small and not noticeable. The Earth is so massive that the force of all the people jumping would not be enough to cause any significant movement or change.
If everyone in the world jumped at the same time, the impact on the Earth would be very minimal. The combined force of all the people jumping would not be enough to significantly affect the Earth's rotation or orbit. The Earth is much larger and heavier than all the people on it, so the effect would be negligible.
Newtons Law "III. For every action there is an equal and opposite reaction. " shoing that if every one did jump it would have an effect on the Earth but not enough to have a major effect on the planet. So everyone jumping at the same time will have no effect on the earth since the earths mass to so large it will have no effect.
No, but you could attempt it and see what happens. LOL
No.
It depends. if they're all in the same area, it would be like someone punching the earth. The amount of weight of all the people, is how much force would be apilied. if the weight of the people is higher then the weight of earth, it would go flying through space.
Yes. Everyone on earth for whom the moon is visible sees the same phase at the same time.
No, the earths orbit is so great that the moon would would half to go at 100,000 mps to alter the orbit of the earth.
Yes, they are. All custom made calendars will be unique since not everyone is the same. No person will have the exact same thing as another person since not everyone has the exact same personal preference.
When you jump in the air, you already have the same momentum as the spot you jumped from because you and the earth are moving together. The Earth's rotation doesn't affect your jump because the atmosphere moves along with the Earth as well.
Everyone on earth sees the same face of the moon.
No. It all depends or size and sex of the person.