Calculating Horse Power of Water in Hose

  • Context: Undergrad 
  • Thread starter Thread starter charter504
  • Start date Start date
  • Tags Tags
    Hose Power Water
Click For Summary

Discussion Overview

The discussion revolves around calculating the horsepower of water contained in a hose with specific dimensions and a vertical height. The focus includes concepts of potential energy and the relationship between energy and power, as well as the implications of the hose's geometry on these calculations.

Discussion Character

  • Technical explanation, Conceptual clarification, Debate/contested

Main Points Raised

  • One participant asks how to calculate the horsepower of water in a hose that is 1" in diameter and 7 ft long, with a U section 4 inches high.
  • Another participant explains that a static vertical tube does not expend energy but has potential energy calculated as mgh, suggesting that the average height of the water column is 3.5 ft, leading to a potential energy of 8 ft-lb.
  • A different participant questions the calculation of 8 ft-lb and asks for clarification on the term mgh and its units.
  • One participant suggests calculating the volume of water in the hose and using the weight density of water to find the potential energy, emphasizing the importance of consistent units.
  • Another participant clarifies that horsepower is a unit of power, not energy, prompting further inquiry about the energy value.
  • One participant reiterates the potential energy value of 8 ft-lb as calculated by another participant.

Areas of Agreement / Disagreement

Participants express differing views on the calculation of potential energy and the interpretation of horsepower versus energy. There is no consensus on the correct approach or final values, and some participants seek clarification on the concepts involved.

Contextual Notes

There are unresolved aspects regarding the assumptions made in the calculations, the definitions of terms used, and the specific conditions under which the energy and power are being discussed.

charter504
Messages
4
Reaction score
0
if i have a hose that is 1" in diameter, and 7 ft long before coming to a U section 4 inches high, and I have this hose full of water standing vertically, how much horse power does this hose of water contain?
 
Physics news on Phys.org
Power is a rate of energy expenditure. A static vertical tube is not expending any energy, but it does have a potential energy due to the height of the water column. Potential energy is just mgh.

I don't understand what you are saying about the geometry of the hose, so I can't help you calculate the energy in it. However, if the hose were completely vertical, the average height would be 3.5 ft and the potential energy 8ft-lb.

[edit] Since 1 horsepower is 550 ft-lb/sec, if the hose emptied in one second, it would generate an average of .016 horsepower for that second.
 
I don't know how you get 8 ft lbs. can you explain? and what is mgh and why is it only in that unit?
 
Multiply the area of the hose by the length to get volume (be sure to convert to cu ft). The weight density of water (already has "mg" in it) is 62.4 lb/cu ft. Average height 3.5. Multiply that all out...

m=mass
g=gravitational acceleration
(put them together and you get weight)
h=height

Units are whaver you want (I used what you used), just keep them consistent.

[edit] Oops, wait - this isn't homework, is it?
 
no its not homework. I just need to know how much hp is potential energy in this hose.
 
Horsepower is a unit of power, not a unit of energy.
 
well then how much energy is it?
 
8 ft-lb. As russ watters calculated above.
 

Similar threads

  • · Replies 11 ·
Replies
11
Views
4K
  • · Replies 17 ·
Replies
17
Views
2K
  • · Replies 32 ·
2
Replies
32
Views
12K
  • · Replies 6 ·
Replies
6
Views
3K
  • · Replies 10 ·
Replies
10
Views
5K
  • · Replies 9 ·
Replies
9
Views
2K
  • · Replies 27 ·
Replies
27
Views
3K
  • · Replies 4 ·
Replies
4
Views
4K
  • · Replies 13 ·
Replies
13
Views
19K
  • · Replies 20 ·
Replies
20
Views
11K