Imagine you could dig a well right through the earth. What would happen to a tennis ball thrown in it?

Question

Imagine you could dig a well right through the earth. What would happen to a tennis ball thrown in it? I have had this question since my childhood, and still can't think of an answer.

Answer 1

It will swing like pendulum from one end of earth to other end assuming that earth heat will not destroy tennis ball and there is negligible air friction.

Answer 2

There are several answers to this question.
1. You cannot dig a well right through the earth.
2. Even if you do, you will not do that to put a tennis ball into it.
3. If the radius of the well is less than that of the tennis ball, the ball will not enter first into that hole.
4. When you dig so deep into earth, water would come out of it and submerge you.
5. Assuming no water or gas came out of it, it would not be called a well. It would be called a hole
6. If you are able to put a ball into that hole, you cannot be sure whether it reached the otherside of the earth. Because by the time you reach there, it might have already come out and some kid would have taken it away for playing with his other buddies.
7. If you reach the other end of the hole and not find the ball, you will never be sure whether it was taken away by a playing kid or it bounced back to the place where you started to dig. If you go back again to the starting point, again the same dilemma. A kid playing with his buddies might have taken it away.
8. And suppose you find out what exactly would happen to the ball thus thrown into the hole, you would be past your middle age, although you started that during your youth. And, you may not find your own family members, including your wife, very appreciative of you for having done such unnecessary things in life.

Answer 3

The central space in the earth is an area with zero gravity. When you drop the ball, it will go down to some extent but will be pulled back to the surface of earth where gravitational pull is stronger.The ball will not travel through the entire depth of the well.

Answer 4

being that there is no factual way to completely block up an artificial wall around the molten magma near the core of the earth, the tennis ball would melt halfway down. If it didn't do that, it'd fly up out the other end of the earth, then gravity would reverse its trajectory, causing it to fly up the end it came out of... and it may well do that repeatedly till the friction and other forces cancel eachother out.

Answer 5

It's a serious answer.
1. if the hole is dug through centre of earth, the ball will have simple harmonic motion. it's speed will rise so high that it will burn due to friction with air by the time it reaches centre.
2. if the hole is not passing through centre of the earth, it just won't move inside the hole, since it will have tendency to go to centre & there is no path.

Answer 6

if any one could dig a hole right through the earth to the other side then two players standing on each side can play tennis through the hole.

Answer 7

For a imaginary question the answer is also imaginary only. The ball may be dropped ,but it will not come the other side, because of forces acting on it.

Answer 8

if you can dig a hole through the earth, it would probably not burn in the lava.

In that case it would swing like a pendulum around the center of the earth coz once it reaches there, it gets confused.

Answer 9

Since it is an imaginary question and not a scientific one the answer is very simple :- The ball "may" or "may not" come the other side. Good luck !!!

Answer 10

You may b a kid in 8th std.
The previous answer was funny...
Do you know the motion a simple pendulum..
Or imagin a stone hanging in air tied with a thread,now you pull it and release it.What will happen.