Science offers a reasonable answer
First, let’s think about how many people that would involve. The world’s population is nearing seven and a half billion. That’s quite a lot of people. The average human weighs 60kg, so all of us would weigh around 450,000,000,000kg, or 450 billion kilograms. That seems like a lot, but in perspective, the Earth’s mass is 59,720,000,000,000,000,000,000,000kg, or 5.9 septillion kilograms (aka huge). And considering it would be totally impractical to get every single human on Earth to a specific place to jump together, the force exerted on the Earth with people jumping all over it would be rather miniscule. Maybe there would be a loud crack – but we wouldn’t be headed for a collision course with the moon.
Gordon Lai, 13, Singapore International School
Think of our poor feet
I think it would make a huge noise. And the hospitals would be super busy the following day, because lots of old people would hurt their feet jumping!
Michael Kwok Pui-hin, 15, Law Ting Pong Secondary School
I think there would be an earthquake because nowadays there are lots of single people, if “single person” also includes widows and widowers.
Ally Tsang , 14, St Paul’ s School (Lam Tin)
A light load
Nothing would happen because humans are very light compared to the Earth – it’s not like our tiny bodies could cause an earthquake!
Jennifer Shon, 14, PLK Ma Kam Ming College
Seven billion people ... all jumping at the same time – the idea doesn’t sound too pleasant. That’s a lot of energy, and let’s not even talk about the sound it would create, especially the applause afterwards. I think the Earth might even move a little, and all the bridges would collapse!
Anushka Purohit, 16, Renaissance College
All jump together now
I don’t think anything would happen, as the Earth would just go back to its original position once everyone landed. What I would want to happen though, is for everyone to get together on one side of the planet, as close to one spot as we could, and all jump at once – maybe it would move Earth?
Liam Fung, 15, Chinese International School
End with a bang
It would probably be the end of the world because humans are pretty heavy these days, and we’d shake the Earth to its core.
Eunice Yip, 16, Pooi To Middle School
An interesting theory
I imagine the world would become smaller, because having seven million people jump at the same time would reduce the land area. The consequences would be interesting – it would take only four hours to drive from Hong Kong to Beijing. You would be able to drive across Africa in just a day. The Pacific Ocean would shrink, meaning that islands would be closer to each other. Hawaii would shift towards California, making it only a few minutes away from Los Angeles. London would be closer to Iceland and plane journeys would be much shorter.
Timothy Tang, 14, King George V School
It wasn’t me
My sister would turn to me and say, “You really need to do something about your farts”.
Catherine Wang, 17, Chinese International School
It’s no big deal, really
Well, nothing SIGNIFICANT would happen. The effect of seven billion people jumping together may not be as strong as an earthquake, but who knows, there might be a little change. But either way, I’m sure SOMETHING would happen, so it would be interesting to find out!
Helen Wu, 19, University of Hong Kong
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