# If a hole is made right through Earth so it reaches the other side, what will happen when one jumps into it?

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• marco
Lv 5
3 years ago

Assuming there's no air resistance, death from the intense heat at the center of the earth, etc.: not only do you fall, but you continue to accelerate all the way down to the center. However, your rate of acceleration decreases, because there's less mass between you and the center of the earth to keep pulling. The rate of acceleration decreases when you hit the exact center: the earth is pulling equally on you in all directions.

But you still have momentum. In fact, the momentum reaches its maximum at exactly the center of the earth. Not only do you not stop, you're going faster than ever, and you sail right through the center.

At that point, though, the acceleration reappears. It's still pulling you to the center of the earth, so it's in the opposite direction of your momentum. This means that instead of getting faster, you're getting slower.

You'll continue to go slower and slower, and your momentum will hit exactly zero at precisely the point where you pop up at the surface of the earth, 180 degrees from where you started (and 42 minutes later).

As a double-check, let's look at the conservation laws. You started with no momentum at the instant you jumped into the hole, and now you have no momentum again. You started with the potential energy of being 4,000 miles above the center of the earth, and you have that same potential energy again, only on the opposite side of the planet. So everything checks out.

(Everything is conserved during movement, too. Handling the conservation of energy while you're moving is easy; the potential converts to kinetic, and back. Dealing with momentum is a little hairier, since you need to consider the momentum of both the earth and yourself, which is kind of a pain. Trust me that the math works.)

• 3 years ago

it depends where the hole is. if it is the middle to the earth north pole to south pole then Earth would be no more

• 3 years ago

Great question

Providing the hole has a protective shied all the way through and you had a frictionless Vessel.

You would fall at the acceleration of Gravity ( 9.81 m/s ^2) to the centre of the Earth

There you will be at your maximum Velocity as Gravity reverses

Once you have crossed the centre you will slow at the same rate until you stop at the other side exactly 45 minutes exactly (Work it out)

You would need to put on the Handbreak though as you would repeat and do the opposite till where you began or even bounce back and forth In perpetual motion

Physically it would work and Engineering wise Nothing is impossible

Such a franchise does not need to go through the centre of the Earth but going in a straight line through Earth still takes 45 minutes wherever it is

Down, then up

• 3 years ago

If you start that hole in he continental US, you will end up in the Indian Ocean, and LOT of people will be very angry when that ocean starts to drain into the hole.

• Jay R
Lv 7
3 years ago

One would die. Next.

• Athena
Lv 7
3 years ago

You will die from the pressure less than a quarter way down.

• 3 years ago

In theory you would just fall through, accelerating until you reached the centre and decelerating as you approached the other side, then fall back in the same manner ad infinitum. It's an unusual orbit, roughly. In reality there would be other factors involved such as terminal velocity and not falling perfectly straight which make it impossible. It would take 43 minutes to fall through the Earth.

• John P
Lv 7
3 years ago

One would stop at the centre of the Earth - rather hot!

• 3 years ago

vapourization due to the immense heat long before you even reached the centre.

air pressure would increase with depth in the hole. Due to the gas laws, temperature would also increase. Not sure of exactly when it would happen but I suggest that before you got a hundred miles down you would become a cloud of compressed vapour at a temperature of several hundred degrees..

Oh and btw, you would never get anywhere near the centre. The air would become so dense and viscous that the little cloud of vapour that was you would come to a standstill and just float there probably only a couple of hundred miles down the hole.

Cheers!

• 3 years ago

First it would pull a lot of the atmosphere inside where it would condense near earth's core. If you jumped in, you'd probably hit the side and bounce around like a ping pong ball, with bloody results, unless your trajectory was exactly perfect. Even if it was, you'd freefall until you reached terminal velocity where air friction has as much force as gravity. That's around 160 mph at sea level. The air would get denser and hotter as you approached earth's core, however. I don't know if you'd be crushed first or burn up.

• 3 years ago

Assuming they are not seared to a crisp, they will continue to accelerate until the past the centre of gravity and decelerate and stop when they will nearly reach the other side.

BUT there is also terminal velocity in which you will continue to travel back and forth until you stop at the centre.