Homely Scientist

The next question I’m going to answer is about the composition of the Earth and the fundamental force we all know an love … gravity.

So the question comes from Deb, a fellow b5 blogger at the Tangled Thread:

My son’s class is studying about various forces right now. His question at dinner last night was a two-parter: As you get closer to the center of the Earth, does it get hotter? and Does gravity pull harder the further underground you go?

First part … does it get hotter as you get closer to the centre of the Earth?  You bet!  The Earth’s core is over 5000 deg centigrade or about 9700 deg Fahrenheit!  Man that’s hot!

The Earth is made up of the crust (that’s what we’re on) the mantle (molten and where the magma is that comes out as lava), the outer core, and inner core.  As you get deeper hot only does it get hotter, but the pressure increases as well.

Wikipedia has a great article on the structure of the Earth … a good read.

Now gravity increasing as one gets closer to the centre of the Earth … thus far I haven’t been able to find a specific answer to the question, but looking up gravity on Wikipedia, leads me to believe that my initial thinking was correct … no it’s a constant.

But … that certainly was a very thought provoking question for me!  We know that gravity pulls us all toward the centre of the Earth (and we actually push back, but our individual gravitational force is tremendously weak … which is why the Einstein quote "Gravity cannot be blamed for people falling in love" is so funny).  So wondering if the force increases as you get closer is a bang on great follow up!

Keep those questions coming!  Leave a comment or send them directly to tris AT b5media DOT com!

Tags: gravity, geology, earth structure, crust, mantle, core

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