IGCSE/GCSE/O & A Level/IB/University Student Forum

Qualification => Subject Doubts => GCE AS & A2 Level => Sciences => Topic started by: Darkstar3000 on January 01, 2010, 01:27:33 pm

Title: How do i solve these questions (fluids/ Fluid flow)
Post by: Darkstar3000 on January 01, 2010, 01:27:33 pm

These were the questions given to me by my teacher but i can't get it!

1.Calculate the pressure difference between the two ends of a hosepipe 20cm long and radius 0.5cm if the rate of flow of water through it is 0.8 litres per second. ....viscosity of water = 1 x 10(to the power -3)


2.Oil flows steadily through a uniform pipe of length 2m and internal diameter of 1.0cm . If the flow rate is 8.5 x 19(to the power -6)m(cube)/sec calculate the pressure difference between the ends of the pipe... viscocity of oil = 0.01 NS/m(square)

EDEXCEL

Title: Re: How do i solve these questions (fluids/ Fluid flow)
Post by: vanibharutham on January 01, 2010, 01:53:01 pm

i have NO idea how to solve either question,

but i think i may have a guide for the first one....

is this for EDEXCEL or CIE

Have you heard of Bernoulli's Equation? maybe that might help

Title: Re: How do i solve these questions (fluids/ Fluid flow)
Post by: astarmathsandphysics on January 01, 2010, 02:07:20 pm

dp/dx=8vQ/(pi*r^4) where v is viscosity

then pressure difference=0.2 * this answer

Title: Re: How do i solve these questions (fluids/ Fluid flow)
Post by: Darkstar3000 on January 01, 2010, 04:37:06 pm

Quote from: astarmathsandphysics on January 01, 2010, 02:07:20 pm

dp/dx=8vQ/(pi*r^4) where v is viscosity

then pressure difference=0.2 * this answer

what is dp, dx and Q

Title: Re: How do i solve these questions (fluids/ Fluid flow)
Post by: astarmathsandphysics on January 02, 2010, 06:27:56 pm

dp is pressure difference
dx is length of pipe and Q is rate of fluid flow