# Science Questions

## If the Earth stopped spinning, would things get heavier?

Sun, 24th Jun 2012

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### Question

Hello!

I know that the rotation of the Earth creates centrifugal force that counteracts the force of gravity.

If the Earth stopped spinning, how much heavier would things become?

Would we all be crushed by the force of gravity?

Thanks so much!!!

Regards,

Rex

#### Make a comment

The reduction in weight at the equator due to Centrifrugal force (sorry Geezer) amounts to 0.35% and is of course zero at the poles. syhprum, Thu, 14th Jun 2012

Of course, without the spin, the Earth would not have an equatorial bulge.  If the spin suddenly stopped, perhaps the bulge would rearrange itself quickly.  Anyway, without the bulge, the gravity would be higher than calculated at the equator, and less than calculated at the poles. CliffordK, Thu, 14th Jun 2012

Far be it for me to burst anyone's bubble. Should they wish to believe in the Tooth Fairy, the Easter Bunny, and the Solstice Amphibian, that's entirely up to them, but this is a science forum, so those who choose to refer to forces centrifugal might at least point out that these are pseudo-forces.

They seem very real, but they are actually imagined (just like the Tooth Fairy, the Easter Bunny, and the Solstice Amphibian). Geezer, Fri, 15th Jun 2012

I only used the dreaded C word because that is how the originol correspondent refered to the centripetal acceleration as you may surmise he was rather confused as to magnitude of this effect. syhprum, Fri, 15th Jun 2012

Good point!

For the benefit of the correspondent, we can state that gravity produces a centripetal force (acting towards the center of the Earth) and that centripetal force can be reduced slightly because our mass would prefer to follow a tangential path relative to the Earth's surface - IOW, it would prefer to go straight on, but in this case, gravity wins, so we stay "attached" to the Earth.

This naturally prompts another related question:

How short would the terrestrial day be if objects at the equator did not stay attached to the Earth?
Geezer, Sun, 17th Jun 2012

Assuming Earth was solid and didn't deform, (which it would as it's mostly liquid / ductile), 84 minutes ...

http://exploration.grc.nasa.gov/education/rocket/rktrflght.html

Wikipedia makes it 85 minutes ... http://en.wikipedia.org/wiki/Orbital_speed#Earth_orbits RD, Wed, 20th Jun 2012