# Physics: Dimensional Analysis Question (Newtons Second Law)

• Aug 29th 2009, 03:50 PM
SMA777
Physics: Dimensional Analysis Question (Newtons Second Law)
Hi everyone, I have a quick question about a HW question for Physics.

The question asks: If acceleration = force/mass (aka Newton's second law), what are the dimensions of force ?

So far, what I have is a=f/m, then f = a*m, so f = [L]/[T]^2 * m
However, no where in the book am I able to find the dimension of mass. Would it just be [M] ?

Thanks for your help!
• Aug 29th 2009, 05:37 PM
mr fantastic
Quote:

Originally Posted by SMA777
Hi everyone, I have a quick question about a HW question for Physics.

The question asks: If acceleration = force/mass (aka Newton's second law), what are the dimensions of force ?

So far, what I have is a=f/m, then f = a*m, so f = [L]/[T]^2 * m
However, no where in the book am I able to find the dimension of mass. Would it just be [M] ?

Thanks for your help!

Yes. Read this: Dimensional analysis - Wikipedia, the free encyclopedia
• Aug 31st 2009, 12:08 AM
CaptainBlack
Quote:

Originally Posted by SMA777
Hi everyone, I have a quick question about a HW question for Physics.

The question asks: If acceleration = force/mass (aka Newton's second law), what are the dimensions of force ?

So far, what I have is a=f/m, then f = a*m, so f = [L]/[T]^2 * m
However, no where in the book am I able to find the dimension of mass. Would it just be [M] ?

Thanks for your help!

The fundamental dimensions in dimensional analysis are mass [M], length [L] and time [T], these are what a dimensional analysis should be expressed in terms of.

CB
• Aug 31st 2009, 11:48 AM
SMA777
Thank you both very much :)