question for smart people
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- mikotondria30
If it accelerated linearly, then we can say that it took twice the time that it would have taken were it travelling at its fully speed...
So, 600feet at 50mph = 50/60(5280)/60seconds = 73.33 feet per second, so 600/73.33 = 8.1821901 seconds, * 2 =
16.3643802 seconds.
This assumes it accelerates in a perfectly linear fashion.
It is simply the area under the time distance graph, which - because it starts at 0 and ends at 50mph, is simply a traingle with half the area of the time/distance graph were it at 50mph the whole time.
- 7point340
7.34 is my final answer
- Amicus0
t=(v-iv) / a
t = time
v = velocity
iv = initial velocity
a = accelerationwe only have v and iv... we don't know the rate of acceleration and therefore can't work out the time.
- we've decided to assume acceleration is constantribit
- you aren't using all the dataribit
- that's an erroneous assumption.Amicus
- we just want to get rid of this and move on. (It cant be solved at all if we don't assume constant acceleration)ribit
- that's my pointAmicus
- no it wasnt.ribit
- If acceleration is constant it can be solved.ribit
- because we know the distanceribit
- dibec0
I just work here.
- CALLES0
can i use a help line?
- mikotondria30
I have given, and explained the correct answer.
This thread must cease at this point.
I r correct.
- harlequino0
miko:
"If it accelerated linearly, then we can say that it took twice the time that it would have taken were it travelling at its fully speed..."How can we know that? We do not know what object we are dealing with, and its accel rate. Could be Ferrari, could be a homemade scooter. We don't know what it's rate is.
- it's one of CALLES' gigantic balls7point34
- lefty i think7point34
- righty isn't much for competition7point34
- Yes. Poor little prune that it is.harlequino
- We have to assume linear acceleration, OR throw out the question as unsolvable. So we are done.ribit
- Amicus0
it is almost impossible for an object to accelerate linearly from rest. The assumption is erroneous.
- uberdesigner0
I'm like barbie-math is hard
- drgss0
90.4 seconds/h
- ribit0
The guys from Sciencetoday are gonna just love this thread...
- did you send them the link?
in that case: sciencetoday is a bunch of queers!7point34 - We should crash their messageboard and fuck their shit UP.harlequino
- i am THERE!7point34
- did you send them the link?
- vaxorcist0
??? hmmm linear or nonlinear acceleration.... this depends on tire traction, delays while switching gears,etc...
That and the calculus I forgot... I could ask my dad, he's a Physics Professor... but here's my guessing game:
We can gently extrapolate from 1/4 mile times..
For example, a Lexus IS350 supposedly runs 14 second quarter miles at 100MPH at the end....
http://www.lexustech.org/Perform…
1/4 mile is 1320 feet (5280 feet / mile)
The object (possibly a car, possibly something totally different) is supposed to go 0-50 in 600 feet.
600 feet is a bit less than half of 1320 feet.
This lexus goes 0-60 in approx 5.3 seconds, therefore we can make a reasonable guess that the "car" or object in question has a similar trajectory rate, therefore it's about 4.8-5 seconds.
Assuming it is a car with fairly predictable rate of car-like acceleration.... no spinning tires,etc....
- Jnr_Madison0
4.75145411554458945455455
- Amicus0
c'mon guys. we all know that to assume makes an ass outta u and me
- mikotondria30
My god, I hope noone I know is reading this board, it's embarrassing..
If a car is going at 25 miles an hour over a distance, then that is the same as if it was going half the time at 0, and half the time at 50.
Right ?
So that is that same as if it was going FROM 0 to 25 (at the mid-point - this being our constant linear acceleration assumption), THEN from 25 to 50 to 'make up' for the slower 1st half.
The graph is a straight line from 0 to 50. This is the same area as if it were a straight line across from starting at 25, and ending at 25.
SO, the time is the time taken to go 600 feet at 25 miles per hour.
- harlequino0
^But that is like saying "A Ferrari takes 5 seconds to go 0-50. A Pinto will take 30 seconds to go 0-50. Despite this baffling difference in auto engineering, both vehicles will get to 600 feet in distance at the same time."
- well, only if both cars are moving at 50mph, if that's true, then yes, both will go 600 feet in the same amount of timevaxorcist
- but they are NOT. Each i accelerating at unknown rates.harlequino
- dude, thats just so seriously wrong... honestly...5s til 50 is NOT the same as 30s to 50. You just said it yourself...mikotondria3
- chossy0
I can tell you that my car would take about one half of a second to fly past 600 feet :D
- doesnotexist0
you're accelerating from 0 to 50 and you don't give us how long that takes? it's impossible for an answer.