Physics question.

This is rocket science. :D

[video=youtube;Jev89sptkbg]https://www.youtube.com/watch?v=Jev89sptkbg[/video]
 
Sinbad said:
The car is secured on a dyno when being tested. The rocket will not make the car move.
The rocket would make a car move on the road. Motion of the car will cause the wheels to turn.
Unless you're thinking of an unsecured car on something like a treadmill?
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The rocket would transfer energy to the car making it move. Because the wheels are not frictionless they would turn regardless of being on the road or a dyno. But because the rocket transfers energy to the car directly and not to the wheels it would also propel the car forward. If this force is greater than that of gravity the car won't continue to fall back into the pit of the dyno and will eventually go off it.
 
Swa said:
The rocket would transfer energy to the car making it move. Because the wheels are not frictionless they would turn regardless of being on the road or a dyno. But because the rocket transfers energy to the car directly and not to the wheels it would also propel the car forward. If this force is greater than that of gravity the car won't continue to fall back into the pit of the dyno and will eventually go off it.
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Cars on dynos are tied down.
 
Oh no, we are back to the plane on the treadmill issue :p
Same answer btw, the plane will take off, the car's wheels wont turn if it's tied down. In both cases the wheels become auxiliary. They are not transferring power, they merely keep the craft up. All thrust is being delivered by the prop/rocket.
 
Nuro said:
Oh no, we are back to the plane on the treadmill issue :p
Same answer btw, the plane will take off, the car's wheels wont turn if it's tied down. In both cases the wheels become auxiliary. They are not transferring power, they merely keep the craft up. All thrust is being delivered by the prop/rocket.
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That^^^ Car and dyno become one system when tied together, either the whole dyno would move OR the straps break and the car takes off OR the rocket fires and everything stays put. What will NEVER happen is the wheels start turning on the dyno.
 
I think Rickster's question related to the car on the dyno itself. Not qualifications of it being tied down as a car-dyno unit.
 
Swa said:
I think Rickster's question related to the car on the dyno itself. Not qualifications of it being tied down as a car-dyno unit.
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Read my post regarding the equivalent of a treadmill type thing without a tie-down.
 
Sinbad said:
Cars on dynos are tied down.
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If the absolute size of the rocket is larger than the square of the hypotenuse of the dyno, and the relative weight of the car is less than half the length of the force exerted by gravity on the circumference of the combination of the two objects times pi, then say goodbye to both your car and the dyno.. (even tho the wheels still won't turn).
 
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Do the wheels on a aeroplane's landing gear spin while the jet engines are propelling it through the air?
 
Rickster said:
If you attach a rocket booster onto a car and put that car onto a dyno, then fire just the rocket.

Would the wheels turn?
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Speed = Distance ÷ Time.

The Speed of the wheels is dependent on both Distance and Time. Assuming the vehicle is tied down and the engine is not running, then you have one missing variable...Distance. So no.
 
I can't believe that something as elementary as this needs to be explained to anyone older than about four years old...
 
Colin62 said:
I can't believe that something as elementary as this needs to be explained to anyone older than about four years old...
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you won't believe how many people can't get their heads around things like this.
I remember once a massive argument about placing a model plane on a treadmill that moved backwards at the same speed as the plane moved forward, would it be able to take off - and people were adamant that it wouldn't.
 
Sinbad said:
you won't believe how many people can't get their heads around things like this.
I remember once a massive argument about placing a model plane on a treadmill that moved backwards at the same speed as the plane moved forward, would it be able to take off - and people were adamant that it wouldn't.
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I suppose we all have different strengths.

(That's my PC act of love for the day out the way, back to being bitchy now).
 
Colin62 said:
I can't believe that something as elementary as this needs to be explained to anyone older than about four years old...
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I used to think like this, once upon a time. However years of browsing through stupidity and ignorance online have lowered my expectations dramatically.
 
Colin62 said:
I can't believe that something as elementary as this needs to be explained to anyone older than about four years old...
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Trick is phrasing it in a way that would make sense to a four year old (or whatever). That's where I seem to struggle.
 
There's a Delta Motor Corporation of South Africa Opel Monza 160i GSi Car of the Year 1991 joke in here somewhere...
 
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