You are Here: Home >< A-levels

# Thermofluids help Watch

1. Oilof relative density 0.8 flows at the rate of 216000m3/s through afalling pipe which tapers gradually in the direction of flow. The diameter at apoint A is 0.6m and at point B, 3.6m vertically below A, it is 0.3m.
1. The gauge pressure at A is84kN/m2. Calculate the pressure at B. Ans. 109kN/m2 gauge
So what i did first was USE the continuity equation to find the velocity of A and B
Volumetric flow rate/pi(r)^2 = velocity

and then i just inputted it into bernies equation

3.6 + (84*10^3)/9.81*800 + (7.639*10^5)^2/2*981 = 0 + P/(800*9.81) + (3.0558*10^6)^2/(2*9.81)

rearranged to find p at b and it's always wrong, what am i doing wrong? the 7.639 and 3.0558 are the sppeds i calculated
2. i keep getting a negative answer

TSR Support Team

We have a brilliant team of more than 60 Support Team members looking after discussions on The Student Room, helping to make it a fun, safe and useful place to hang out.

This forum is supported by:
Updated: May 21, 2016
Today on TSR

### Should I ask for his number?

Discussions on TSR

• Latest
• ## See more of what you like on The Student Room

You can personalise what you see on TSR. Tell us a little about yourself to get started.

• Poll

## All the essentials

### Student life: what to expect

What it's really like going to uni

### Essay expert

Learn to write like a pro with our ultimate essay guide.

### Create a study plan

Get your head around what you need to do and when with the study planner tool.

### Resources by subject

Everything from mind maps to class notes.

### Study tips from A* students

Students who got top grades in their A-levels share their secrets

## Groups associated with this forum:

View associated groups
Discussions on TSR

• Latest
• ## See more of what you like on The Student Room

You can personalise what you see on TSR. Tell us a little about yourself to get started.

• The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.

Register Number: 04666380 (England and Wales), VAT No. 806 8067 22 Registered Office: International House, Queens Road, Brighton, BN1 3XE