Dimensions related to Planck's constant H

AI Thread Summary
The discussion revolves around deriving new quantities from the fundamental constants: the speed of light (C), Planck's constant (H), and the mass of the proton (M sub p). For part A, the correct combination to yield dimensions of length (L) is H/(M*C), while for part B, the combination for dimensions of time (T) is H/(M*C^2). The original poster expressed confusion but ultimately confirmed their calculations were correct. Additionally, they sought further assistance on a separate topic regarding FCC fraction packing in a pyramidal structure. The thread highlights the collaborative nature of learning in physics forums.
ODBS
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Consider a system where the three fundamentally important quantities are the speed of light C with dimensions (L)/(T), Planck's constant H with dimensions (M)(L)^2/(T), and the mass of the proton M sub p with dimension (M).
a) What combination of ratios and/or products of C, H, and M sub p will yield a new quantity of dimensions (L)?
b) What combination of ratios and/or products of C, H, and M sub p will yield a new quantity of dimensions (T)?


I have no idea how to figure this out. I am brand new to physics so any help would be greatly appreciated. Could you please solve the question and walk me through how you found the answer? I am a very literal learner and I need to see the answer along with how you found it.




This is what I came up with, not sure if it's correct:

(C^a)*(H^b)*(M^c)

L^(a+2b)=L----> a+2b=1
M^(b+c)= 1-----> b+c=0
T^(a-b)=1---->a-b=0

a=-b
b=1
a=-1
c=-1

(C^-1)*(H^1)*(M^-1)=H/C*M

-a-b=1
a+2b=0
b+c=0
b=1
a=-2
c=-1

So, H/M*c*c


part A= H/M*C
part B= H/M*C*C
 
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:approve: yes, you are correct...I checked it myself. Cheers :smile:
 
Thank you! I've asked another question about fcc fraction packing for a pyramidal structure. Can you take a look at it and help me out? I'm really lost on that one.
 
ODBS said:
Thank you! I've asked another question about fcc fraction packing for a pyramidal structure. Can you take a look at it and help me out? I'm really lost on that one.

I would've if I myself had any clue!:-p I am a student myself, I am not proficient with that topic!...I am sure others will help out! :smile:
 
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