If a car is going 50km/hr and stops in 0.3km, how long does it take the car to stop?
If a car is going 50km/hr and stops in 0.3km, how long does it take the car to stop?
Linear deceleration? Ignore effects of friction, aerodynamics etc.?
>stops in 0.3km
>how long does it take the car to stop?
I'd say 9292,4km
>Ignore effects of friction, aerodynamics etc.?
>implying any of that matters
it will take at least 21.6 seconds.
twice the time it would take to drive the 300m without stopping
Of course it does. The way a car breaks is heavily dependent on its tires and its shape.
About 0.3 km
~1.19882076 s
I think it's 43.6 seconds
what am I doing wrong here?
is the half obsolete?
43.2*
Let's say the car halves its speed until it gets to 0.150 km then halves that speed until gets to 0.175km, then halves that speed until it gets to... etc
The car will never arrive at 0.3 in finite time
yup
you know:
s=a*t^2/2
and:
v=a*t
juggle:
a=2s/t^2
a=v/t
subtract:
0=2s/t^2-v/t
juggle:
v/t=2s/t^2
v*t=2s
t=2s/v=43.2 s
144 seconds
But if the car drives 0.1 km then 0.2 km then 0.3 km etc, it will have stopped 0.008333... km behind where it started
so it IS 43.2 seconds? I don't see anything wrong with my calculations
Bout tree fiddy
yes
>implying it doesn't
a car could crash-brake to 1 km/hr as quick as it possibly can and then bleed off velocity as slowly as it can before it stops at 0.3 km
or it could crash-brake at the last possible second
or it could uniformly decelerate
all of those will have different times
But already specified "linear deceleration", which takes care of all that variability.
>its a OP baits with a vague problem, that has multiple right solutions episode
1 plank time.
Enjoy your destroyed universe, faggot.
v=50-(50/T)t
d=50t-(25/T)t^2+C
0=50(0)-(25/T)(0)+C
0.3=50T-(25/T)T^2
T=0.012 hours = 43.2 seconds
YOU GUYS ARE SO SMART WITH THIS KINDERGARDEN TIER PROBLEM.
>KINDERGARDEN
you either need to know calculus or use the disassemble acceleration in the third standard formula
You don't need to know calculus to find the area of a triangle.
you need it to know that the integral of velocity is acceleration, and that the area under a curve is the integral
Doesn't matter, this "level" of calculus is for 15yo kids.
>linear function
>curve
what did he mean by this?
That post at was asking whether to assume linear deceleration, not specifying it.
nice job spelling kindergarten wrong
>the integral of velocity is acceleration
Forgot to mention, this proved my point
>kindergarden thread
Fuck spelling in foreign languages
this question is too hard
is it 100 seconds?
what is acceleration anyway if not a figment of our imagination
acceleration doesnt exist except in our minds