Problem with Pressure Equation units

  • #1
5
0
I was doing a problem that required me to initially find the amount of pressure that was acting on a bubble, I decided that I had to use the equation P=P(STP) + ρgd. But looking at the equation, the units for the ρgd part of the problem doesn't make sense about how that gives me a unit of pressure (Pascal).


2. So I worked it out and:

ρ= kg/m^3
g= m/s^2
d= m

when multiplied together your units become kg/ms^2 which you are then adding to a pascal unit. So my question really is, is 1 kg/ms^2 = 1 Pa?

An explanation would be much appreciated!
 

Answers and Replies

  • #2
SteamKing
Staff Emeritus
Science Advisor
Homework Helper
12,798
1,670
I was doing a problem that required me to initially find the amount of pressure that was acting on a bubble, I decided that I had to use the equation P=P(STP) + ρgd. But looking at the equation, the units for the ρgd part of the problem doesn't make sense about how that gives me a unit of pressure (Pascal).


2. So I worked it out and:

ρ= kg/m^3
g= m/s^2
d= m

when multiplied together your units become kg/ms^2 which you are then adding to a pascal unit. So my question really is, is 1 kg/ms^2 = 1 Pa?

An explanation would be much appreciated!

1 Pascal = 1 Newton / m2

1 Newton = 1 kg-m/s2 [Using F = m a]

Therefore, 1 Pascal = 1 N / m2 = 1 kg m/s2 × (1/m2) = 1 kg / m-s2

Compare with the units arising from the product ρgd. :wink:
 
  • #3
5
0
Thank you so much! Makes sense now!
 

Related Threads on Problem with Pressure Equation units

  • Last Post
Replies
2
Views
3K
  • Last Post
Replies
7
Views
454
Replies
5
Views
2K
Replies
1
Views
5K
Replies
7
Views
2K
  • Last Post
Replies
7
Views
9K
  • Last Post
Replies
1
Views
3K
  • Last Post
Replies
6
Views
2K
  • Last Post
Replies
9
Views
2K
  • Last Post
Replies
4
Views
1K
Top