IGCSE/GCSE/O & A Level/IB/University Student Forum
Qualification => Subject Doubts => IGCSE/ GCSE => Math => Topic started by: hasan919 on May 15, 2011, 10:00:58 am
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http://www.xtremepapers.me/CIE/Cambridge%20IGCSE/0580%20-%20Mathematics/0580_w05_qp_4.pdf
PG 6 - number 7) c) ii)... anyone can help me wid diz one? Thank You.
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There is a formula for that which is...
Flow of water(volume) = Cross sectional area x speed x time
as we are required to find the time thus the formula changes into:
Flow of water (volume)/Cross sectional area x speed = time
now use the formula to find answer i will post it after i do the whole question :)
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There is a formula for that which is...
Flow of water(volume) = Cross sectional area x speed x time
as we are required to find the time thus the formula changes into:
Flow of water (volume)/Cross sectional area x speed = time
now use the formula to find answer i will post it after i do the whole question :)
By cross sectional area u mean the area of the of the circle(whole pipe) or the semi circle(half pipe)?
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By cross sectional area u mean the area of the of the circle(whole pipe) or the semi circle(half pipe)?
Yes.. :)
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Yes.. :)
I'm asking u mean whole circle or semi?
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I'm asking u mean whole circle or semi?
Yea, i told you its a formula.. that is
Flow of water(volume of whole water) = Cross sectional (volume of the pipe) x Speed x time
can you solve the answer.. i am unable too. in Mark scheme they aren't using the speed in calculation :-\
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Yea, i told you its a formula.. that is
Flow of water(volume of whole water) = Cross sectional (volume of the pipe) x Speed x time
can you solve the answer.. i am unable too. in Mark scheme they aren't using the speed in calculation :-\
No I'm doing m/j 2010 atm
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No I'm doing m/j 2010 atm
ok.. do it later :)
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i keep gettin 436 =/ diz is so confusin =[
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i keep gettin 436 =/ diz is so confusin =[
I do = 1512m3/ .00687m3 x .14m/s = 157205/ (60 x 60 x24) = 18.195 :(
according to mark scheme they do:
1512m3/6870cm3 = 0.220087 x 1000000 = 220087/ (60 x 60 x 24)
i don't know why they at beginning divide a m3 with cm <-- impossible
then don't know why they multiply with 1000000 -.-
:-\
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I do = 1512m3/ .00687m3 x .14m/s = 157205/ (60 x 60 x24) = 18.195 :(
according to mark scheme they do:
1512m3/6870cm3 = 0.220087 x 1000000 = 220087/ (60 x 60 x 24)
i don't know why they at beginning divide a m3 with cm <-- impossible
then don't know why they multiply with 1000000 -.-
:-\
i will explain this part
they divided m3 by cm3, and he multiplied by 100^3 which is 1000000, to conver that m^3 to cm^3
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(1512*100^3) / 6870.
muliplied by 100^3 to convert m^3 to cm^3.
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(1512*100^3) / 6870.
muliplied by 100^3 to convert m^3 to cm^3.
where will speed go?
why not included? :-\
isn't the formula
"low of water(volume) = Cross sectional area x speed x time "
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where will speed go?
why not included? :-\
isn't the formula
"low of water(volume) = Cross sectional area x speed x time "
i just explained, why did they multiply by 1000000
5mins lemme solve it
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i just explained, why did they multiply by 1000000
5mins lemme solve it
Take your time,
If you have doubt search the formula over net ;)
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Take your time,
If you have doubt search the formula over net ;)
thanks :P
okay :P
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Volume of the pool = 1512m^3
1m^3 = 1000000cm^3
1512m^3 = 1512000000cm^3
The pipe transfers pi*12.5^2*14 = 6872cm^3/s
can be written as
6872cm^3 -> 1s
1512000000cm^3 (the whole pool to be transferred) -> ?
1512000000/6872 = 220023.3s
= 220023.3/60 = 3367minutes = 56.11 hours ~ 2.34 days
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220023.3/60 = 3367minutes ?
i get 3667m
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Volume of the pool = 1512m^3
1m^3 = 1000000cm^3
1512m^3 = 1512000000cm^3
The pipe transfers pi*12.5^2*14 = 6872cm^3/s
can be written as
6872cm^3 -> 1s
1512000000cm^3 (the whole pool to be transferred) -> ?
1512000000/6872 = 220023.3s
= 220023.3/60 = 3367minutes = 56.11 hours ~ 2.34 days
By the way, Can you just help me by telling why aren't we using the speed value here when the formula is
"Flow of water(volume of whole water) = Cross sectional (volume of the pipe) x Speed x time "
thanks
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ok here is the answer:
rate of flow per second = pi*12.5^2 * 14 = 6872 cm^3
time in seconds = (1512*100^3) / 6872 = 220023 seconds.
220023/ (3600*24) = 2.54 days.
0,54 * 24 = 13 hours
answer is 2days 13 hours.
same as ghost calcs :)
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ok here is the answer:
rate of flow per second = pi*12.5^2 * 14 = 6872 cm^3
time in seconds = (1512*100^3) / 6872 = 220023 seconds.
220023/ (3600*24) = 2.54 days.
0,54 * 24 = 13 hours
answer is 2days 13 hours.
same as ghost calcs :)
Just someone plz explain me why is everyone excluding the speed value -_____________-
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Just someone plz explain me why is everyone excluding the speed value -_____________-
i used speed.
Rate of flow per second = pipe cross section area * speed
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i used speed.
Rate of flow per second = pipe cross section area * speed
you used length not speed,
volume requires length!
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you used length not speed,
volume requires length!
reread the question
cylinder hight is 14
speed is also 14.
i use the speed to find flow per second
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Ahhh, thanks alot guys. i get it ;]
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reread the question
cylinder hight is 14
speed is also 14.
i use the speed to find flow per second
and if the question included values like:
8 height and speed is 16
so will we use value of speed as 2?
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and if the question included values like:
8 height and speed is 16
so will we use value of speed as 2?
Rate of flow = cross section area x speed.
use 16
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220023.3/60 = 3367minutes ?
i get 3667m
My bad, typo.