Dimensions of Force, Pressure: F, p

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The discussion focuses on determining the dimensions of force and pressure using the fundamental dimensions of length (L), time (T), and mass (M). For force, defined by F=ma, the correct dimensional representation is F=ML/T^2, indicating that force is mass times acceleration. Pressure, defined as p=F/A, can be expressed as p=ML/T^2/L^2, simplifying to p=M/T^2. Participants express confusion over the relationships between these quantities and the correct dimensional analysis. The conversation emphasizes the importance of accurately representing physical quantities in terms of their fundamental dimensions.
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From the following defining equations, determine the dimensions of the names physical quantities. Use L to represent the dimension length (distance), T to represent time and M to represent mass.

a) force, F: F=ma, (where m is mass and a is acceleration)
b) pressure, p: p=F/A, (where F is a force (see previous question) and A is an area)

-I can't even attempt to solve this question as I have no idea what the question is asking for.
 
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The question is asking you to write force and pressure all in terms of the units L, T, and M. So for example, velocity is L/T.
 
OK so..

a) would be.. F=M(deltaL/deltaT) ?
b) how can I define A using only L, M or T?
 
No. Think about what you have written for force. That is saying that force is equal to mass times velocity. That is not correct. For part b, an area is simply two dimensions of length.
 
I still don't think I understand because this does not seem correct but..

a) F=M*d(L/T)/dT ?
b) p=M*d(L/T)/dT/L^2 ?
 
Thread 'Correct statement about size of wire to produce larger extension'
The answer is (B) but I don't really understand why. Based on formula of Young Modulus: $$x=\frac{FL}{AE}$$ The second wire made of the same material so it means they have same Young Modulus. Larger extension means larger value of ##x## so to get larger value of ##x## we can increase ##F## and ##L## and decrease ##A## I am not sure whether there is change in ##F## for first and second wire so I will just assume ##F## does not change. It leaves (B) and (C) as possible options so why is (C)...

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