What are the dimensions for a, b, and c?

AI Thread Summary
The discussion revolves around determining the dimensions of unknown variables a, b, and c in the equations F = at + bt² and F = at + bt² + cx³, where F represents force and t and x are time and an unknown variable, respectively. The user successfully derived the dimensions for a and b as MLT⁻³ and MLT⁻⁴, but struggles with c due to uncertainty about the dimensions of x. It is suggested that x could represent length, which would help in finding c's dimensions. However, users emphasize the importance of independently solving homework problems rather than posting complete solutions. The conversation highlights the necessity of understanding the dimensional analysis in physics equations.
NeerajKarthi
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Homework Statement


Equation 1: Find the dimensions of a,b

F = at + bt2
F - force
a - Some unkown value
b - Some unkown value
t - time

In this equation we must find the dimensions of a and b which i did but, in the next similar equation

Equation 2: Find the dimensions of a,b,c

F = at + bt2 + cx3
F - force
a - Some unkown value
b - Some unkown value
t - time
c - Some unkown value
x - Unknown

I don't know how to find out dimensions for c as i don't know what is the dimensions for x here.

Homework Equations


F = at + bt2

The Attempt at a Solution


F = MLT-3

For the 1st equation, i got

a = MLT-3
b = MLT-4

For c= ? I don't know how to find.
What is the dimensions for x also?

Thanks in advance
 
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Is that the only information you have?
Maybe x is in meters (x is sometimes used for length). Otherwise I am pretty sure you can't solve it.
 
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Replusz said:
Is that the only information you have?
Maybe x is in meters (x is sometimes used for length). Otherwise I am pretty sure you can't solve it.
Well, thanks a lot. After checking through i guess x might be length. And can you please post the answer so that i can cross check. Thanks
 
NeerajKarthi said:
Well, thanks a lot. After checking through i guess x might be length. And can you please post the answer so that i can cross check. Thanks
That's not how PF works. You're supposed to work out you own answers. Posting worked out solutions for others on the HW forums is a violation of the rules.
 
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NeerajKarthi said:
F = MLT-3

[Force] = MLT-2
 
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