# Go buddy go!! New question...

Discussion in 'Teacher Time Out' started by kcjo13, Jan 25, 2008.

1. ### kcjo13Phenom

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Jan 25, 2008

If you are driving in an automobile at 60 miles per hour, and you have a fly in your car, is the fly flying at 60 miles per hour to keep up with you?

My first response was of course not. Presumably, the car's windows are up, so the fly is just buzzing around with you as you sit peacefully in your car. But then my hubby pointed out a couple of interesting facts. I'm not telling yet. I want to see what everyone else thinks first!

:2up:

3. ### TeacherGroupieModerator

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Jan 25, 2008

Is the fly MOVING at 60 mph, with respect to the surrounding terrain? Yes, because it's in the car etc. Is the fly FLYING at 60 mph, as in putting in the work required to propel itself at that speed? No.

4. ### Boston1234Rookie

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Jan 25, 2008

If the fly is sitting on the dash board, then he is moving with the car, just like you. If the fly is seemingly suspended in the air while the car is moving the fly is flying at the speed of the car. If you hit the brakes, the fly will crash into the front window because he is moving at the same speed of the car to "suspend" himself and now the car is moving at 0mph but the fly is still moving at 60mph. This is the reason why people get thrown from cars in an accident. The car comes to a sudden stop but the body is still moving at 60mph.

Then again, I took physics a while ago so everything I just said could be 100% wrong.

5. ### RainStormPhenom

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Jan 25, 2008

I hate questions like this ....

just squash the fly, and then you don't have to figure it out, because the fly is dead!

6. ### runsw/scissorsPhenom

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Jan 25, 2008

:2up:

I'd like to see you try to squash the fly while driving! You'd both smack into the windshield when you run into a telephone pole! I think the above posters are right about the fly moving at 60 mph simply because the car is moving that fast and the fly is moving with the car.

7. ### cutNglueMagnifico

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Jan 25, 2008

I think NO but I couldn't tell you why.

8. ### nancy svRookie

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Jan 25, 2008

No. The air IN THE CAR is being transported by the vehicle (yes - a certain amount of air is flowing in and out, but for the most part the air molecules are traveling with the car). That's why you don't feel the wind when you're in your car. Now if you go ride a motorcycle at that 60 mph you are constantly entering into new air. So - a fly in a car is just flying around in the same ol' air from before that happens to be being transported by the car. But if the fly keeps up with you when you ride a motorcycle, then he is flying at that speed.

9. ### TeacherGroupieModerator

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Jan 25, 2008

Similarly, no one would argue, I think, that astronauts in orbit in the space shuttle are RUNNING at 17,500 mph to keep up with the shuttle... though they are certainly being carried along at that speed, along with everything else in the shuttle.

10. ### kcjo13Phenom

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Jan 25, 2008

So I'll tell you what my hubby's point/question was when he asked this question. When we are driving in our motor home, and jump in the air, would we land in the same place? Or would the motor home drive forward, leaving you to land slightly backward? Yes, you are in contained air, but would you land in the same position in the motor home? If you are on a trailer in open air, and jump into the air, you are going to splat on the highway.

Can you see the tie from this to the fly in the car? Hope so...

I think my hubby is getting a kick out of this. He's giving me a headache! Please reply-it'll make him so happy!

11. ### smalltowngalMultitudinous

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Jan 26, 2008

I just get a headache thinking about questions like this! And I'm not witty enough to come up with a smart answer...so thanks, RainStorm, for that answer. It made me laugh!

12. ### TeacherGroupieModerator

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Jan 26, 2008

If you're on a flatbed trailer that's on the freeway and you jump straight up with respect to the trailer, you can land in the same place on the trailer, but the trailer will be in a different place so you'll land in a different place with respect to the ground. If you get pushed backward at all, the only thing that's pushing you backward is the wind, but the trailer would have to be going darned fast for that to make much difference. The trailer doesn't move out from under you. That's a fact about the forward momentum imparted to your body by the trailer.

13. ### AmersCohort

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Jan 26, 2008

Oh, Newton's Laws! I'm teaching these to my fifth graders right now! Unfortunately, I'm so sick of Newton's Laws that I can't even begin to try and decide what the correct answer would be.

14. ### nancy svRookie

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Let's look at the trailer home thing... You are traveling with your trailer at 60 mph. You jump in the air, but Newton's Laws state "an object in motion will remain in motion UNLESS ACTED UPON BY SOME OUTSIDE FORCE." If you were in a flatbed, the outside force would be the air molecules you were running into. However, in a trailer with enclosed air traveling at the speed of the trailer, the air molecules in the trailer are also traveling at 60 mph.

Yes, if you could jump up and stay up long enough for natural forces to do their work (Hey - we can build a conveyor belt as big as a runway, why can't we do this??) gravity and friction would eventually slow you down - you don't have a motor propelling you, while the vehicle does. But you would have to remain suspended for quite some time for that to happen.

15. ### TeacherGroupieModerator

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Jan 26, 2008

Right, nancy sv. I'm not sure even a pole vaulter remains suspended long enough for friction to have a significant effect here.

16. ### eduk8rEnthusiast

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Jan 26, 2008

I'm with you! The logic here is making me dizzy. Rainstorm's answer is the one I vote for.

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Jan 27, 2008

This is too funny!!! Why in the world would anyone want to leave this to go grade papers!

18. ### runsw/scissorsPhenom

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Jan 27, 2008

Let's test it! Mark the floor of the motorhome with tape and stand with your toes touching the tape. Have DH drive down the highway at 60 mph while you jump. Where did you land?

19. ### eduk8rEnthusiast

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Jan 27, 2008

I think you'll land about a foot or so back from where you jumped.

20. ### runsw/scissorsPhenom

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Jan 27, 2008

That'd be my guess. You're still moving with the air in the car, but not as quickly. I keep thinking of some film I saw in hs science. There is a cart rolling on a track and when the front hits a certain point a steel ball falls from above. Because it's moving so fast you think the ball will land on the front end of the car, but it doesn't. It lands on the tail end instead.

21. ### TeacherGroupieModerator

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Jan 27, 2008

If the ball is dropped from outside, yes, it will land farther back. But if it's launched from inside it has forward momentum. If you jump inside a motorhome that's in motion, you'll land exactly where you would if it weren't in motion.

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