Solved: Dimensions of b/a in Pressure Equation

[physics kiddy]

Homework Statement

Assuming that Pressure (P) of a particle is given by

P = b - t^2 / ax

where t = time, x = position
Find the dimension of b/a.

Homework Equations

The Attempt at a Solution

Using dimensional homogenity, I know that b represents time interval.

 

[Infinitum]

Homework Statement

Assuming that Pressure (P) of a particle is given by

P = b - t^2 / ax

Is this (b-t²)/ax or b - (t²/ax)?

If it is the first, there is a subtraction of two quantities. Subtraction of what two quantities gives pressure? What does that tell you about b? and (t²/ax)?

If it's the second, what should be the dimension of b so that (t²/ax) can be subtracted from it? (apples and oranges? or, apples and apples? )

 

[NascentOxygen]

Assuming you have represented the formula correctly ...

Using dimensional homogenity, I know that b represents time interval.

I don't think so.

...

your equation shows P comprising the sum of two components: b and (- t^2 / ax). Those two components must have identical units otherwise you couldn't add them, and what's more, they must have the same units as P.

P = b - t^2 / ax