Who thinks my friend is an idiot? Or was I just stupid to try?

Question

I don't know what catagory to put this question in. I just picked "Travel", because that is what was supposed to happen (but didn't!).

OK. A guy friend from school told me that if you stand in the aisle at the front end of one of the San Diego trolly cars while it is going, and if you jump up in the air 7 times in a row, you will end up at the other end of the trolley car. He explained that this happens because the trolley is moving forward down the tracks while you are in the air, so when you come down after 7 jumps you will be at the other end of the trolley. I was curious, and wanted to try it for myself, and I did when I finally went with him one day on a trolley car that was not very crowded.

I did jump 7 times, but I was still in the same spot exactly. The only thing that happened is I looked pretty stupid to the few passengers. My friend just laughed, and said that It didn't work out because I "didn't do it right"!! Huh!?

Who was more stupid.....me or my friend?

Answer 1

Well, neither of you come off as very bright given your story...:)
Remember Newton's laws of motion, that something in motion will stay in motion unless acted on by an external force? When the trolley started moving, you got the same kinetic energy it did. You're moving along with the trolley. Jump all you want, unless another force acts on you to stop you, you're going to continue to move along with the trolley, feet on the ground or not. It's a good thing, too, otherwise if you were in an airplane at 500+ miles per hour and took a hop in the aisle, you'd hit the back of the plane in no time ;-)
I'll vote for your friend being more stuipd...you were just ignorant!

p.s. I live in San Diego too..

Answer 2

Yes he's an idiot, and you are just gullible to be willing to look foolish enough jumping up and down in a trolley...

Honestly, I'm not a math/science wiz so I couldn't say why it happens, maybe it has to do with the movement of the vehicle in general, but it's the same with a fly on a plane. Would the fly end up slammed/smashed against the back on the plane because it's (the plane) traveling hundreds of miles an hour? Nope, it just flies around in the plane like it doesn't even notice... I guess the air contained within the plane is just moving along with it so nothing is noticeable.

Answer 3

You. Not stupid though. Just a little silly. That is like saying if you jump up on a plane, you will slam into the rear of the plane since it is moving forward at 500mph.

Remember, you are moving forward on the trolley car. It may feel as if you are standing still...but you aren't. You jump "up", you are also moving forward and up. You land in the same place.

So, how was San Fran other than the trolley car ride??? :>

Answer 4

Well i think you're both kind of silly, but what your friend said is actually possible. If the trolley is moving fast enough, and you jump straight up (not a little bit forward) the trolley will keep moving forward faster than your body, and you will seem to move back.
This is due to inertia. I'm not going to go into a long scientific explanation about it, but it's basically the same reason you jerk forward when a car suddenly stops, or you are pushed back in your seat when it accelerates quickly.

Answer 5

Your friend. Remember, you are on a moving trolley moving at the same speed as the trolley. The only way your going to end up at the other end of the trolley, is if you fall down from jumping up and down in the aisle and roll to the other end. lol

Answer 6

I think he's trying to have a little fun at your expense.

You're moving along with the trolley at the same speed. When you jump in the air you are still travelling at the same speed and don't have sufficient time (or drag) to slow down enough while in the air for you to move further back in the trolley.

It's just like if you are sitting in a moving car and you throw a ball straight up in the air. It will fall back into your lap. It won't hit the back window. See?

So, if he's trying to tell you that you didn't do it right, then he's just wanting to see you look silly again. Don't do it! :-)

Answer 7

while the trolley is moving you are moving, even if you are standing still on the trolley. for example, why is it when your in a car, lets say going 30 mph and you slam on the brakes that you (with a safety belt on) are leaning forward or using your abs not to. when the car is moving forward 30 mph. even if your just sitting there, you are going 30 mph. when you slam the brakes, the car dropped speed dramaticly, you on the other hand are still going 30 mph. which is why it is a good idea to wear a safety belt. so when you were jumping on the trolley you were moving at the same speed as the trolley and not enough friction in the air to slow you down. does this make sense to you?

Answer 8

Your friend is "more stupid". Because you are traveling the same speed as the trolly, and because you only achieve air for a few moments each jump, if you jump straight up you will come down right in the same spot. The only way he could have accomplished this was to jump up and forward 7 times, not just up.

Answer 9

He thinks he's pretty smart. It's a classic physics question. The reason why you came down in the same spot is because you were in the same "frame of reference" as the moving trolley car. Think about it. If it didn't work that way, then we could not stay in the same spot when we jumped into the air from Earth.

Since your friend is a smart-a$$, I would recommend retaliation in kind - thinking up an equally annoying experiment and using him as the guinea pig and brunt or your joke.

Answer 10

The trolley is moving you forward at the same speed as the trolley. When you jump, you move forward.

Like when you're in a speeding car, and you suddenly put on the brakes. And you don't have seatbelts.

Your innards splatter all over the windshield.

He said "You didn't do it right!", he's playing with you.