Unanswered Questions on Units in Grade XI Physics

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The discussion revolves around questions related to units in Grade XI physics, specifically the unit represented as [Kg][Meter][Second]^{-3} and the concept of acceleration. The first query seeks the name of the unit, which is analyzed through dimensional analysis, suggesting it could relate to force over time, though no specific name is provided for this unit. The second question addresses the scalar quantity associated with acceleration, with participants noting that while acceleration is commonly used, there isn't a widely recognized term for its absolute value. The conversation highlights the challenges of transitioning to more complex physics concepts and the ambiguity in naming certain physical quantities. Overall, the thread emphasizes the need for clarity in understanding units and their applications in physics.
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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.

Homework Statement


i)What is the name of the unit
[Kg][Meter][Second]^{-3}

ii) What is |Acceleration|

Homework 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| =?

The Attempt at a Solution



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

Thanks for help.

-XuryaX
 
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Welcome to PF.

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

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

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.
 
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|.
 
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