# Few questions about few units

1. Sep 1, 2009

### XuryaX

I am studying in Grade XI and have started with physics. Its very different from physics in last grade. So here are my questions about few units my tution teacher challenged everyone about.
1. The problem statement, all variables and given/known data
i)What is the name of the unit
$$[Kg][Meter][Second]^{-3}$$

ii) What is $$|Acceleration|$$

2. Relevant equations
i) By doing dimensional analysis we get $$[M][L][T]^{-3}$$ , we may also call this Force/Time. Couldn't find anything bout this unit.

ii)
$$|Vector| = Scalar$$
$$|Displacement|=Distance$$
$$|Velocity|=Speed$$
$$|Acceleration| =?$$

3. The attempt at a solution

The above is my try, couldn't do anything further.

Thanks for help.

-XuryaX

Last edited: Sep 1, 2009
2. Sep 1, 2009

### Redbelly98

Staff Emeritus
Welcome to PF.

(i) Looks right. (Are you sure it isn't second-2 ?)

(ii) Acceleration involves something changing ... if you look in your text book, it should have a discussion and an equation or two for acceleration.

3. Sep 1, 2009

### XuryaX

Actually, i just need the name of the physical quantity
MLT-2 is force but is there a name for force/time?

And the Scalar quantity of velocity is called speed, what is the scalar quantity of acceleration?
though we in general use acceleration as ther term in our daily lives.

4. Sep 1, 2009

### RoyalCat

Well, I'm only speaking for myself, but I've never encountered any specific names for these.

The quantity you described in (i) could be the change in force over time. Again, there's no name I've ever encountered for this, since this isn't something of much interest to name.
The change in force over time.

As for the scalar quantity of acceleration, if I wanted to get my point across, I'd call it the change in the speed, that's unambiguous enough.

5. Sep 1, 2009

### Redbelly98

Staff Emeritus
Well, these are rather weird questions. I don't know of any single unit name for force/time. Perhaps they mean for you to take the common metric unit of force (which is ____?) and divided it by seconds.

I missed the "absolute value" sign before. I'm not aware of any term associated with |a|.