Primary Dimension: Mass Units for Power, Pressure, Modulus, Angular Velocity

[jaredmt]

Homework Statement

For each quantity listed, indicate dimensions using mass as a primary dimension and give typical SI and English units:
power
pressure
modulus of elasticity
angular velocity

Homework Equations

The Attempt at a Solution

im not sure i understand what it is asking for. There is another question asking the same thing but with "force" as primary dimension.
with mass being primary dimension, i guess it is referring to MLtT, but that is considered SI units isn't it? so wouldn't i just give examples of SI units? i don't see where english units come in, I am confused

an example of Power in SI is 1 watt = 1 J/s. would that be the correct answer for that part? I am sure this question is easy but I am not clear on what they are asking for

 

[tiny-tim]

For each quantity listed, indicate dimensions using mass as a primary dimension and give typical SI and English units:
power
pressure
modulus of elasticity
angular velocity
…
an example of Power in SI is 1 watt = 1 J/s. would that be the correct answer for that part? I am sure this question is easy but I am not clear on what they are asking for

Hi jaredmt!

I think they're asking for something like ML²/T³ (i made that up! ), watt (that's SI), and foot-pound-horsey-thingy (that's English, or imperial).

 

[Redbelly98]

I agree with tiny-tim. So Force would be ML/T² in this problem, but would simply be F when force (not mass) is a primary dimension.

Don't worry about whether length L is in meters or feet, that isn't relevant here.

 

[nvn]

I agree with Redbelly98, except T should be lowercase t.

 

[Redbelly98]

Typically in problems like this, when one is expressing time units, an uppercase T is used. Just as uppercase M and L are used for mass and length units.

A lowercase t is used to express time as a variable in equations, but that is not what is being done here.

 

[tiny-tim]

I agree with Redbelly98