MHB Understanding Unit Cancellation in Physics Equations

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To solve for 'a' in the equation a = b/e, where b = 1 kg m⁻¹ and e = 1 kg m⁻², unit cancellation is essential. When substituting the values, the kg units cancel out, simplifying the expression to a = 1 m. The calculation demonstrates that the resulting unit for 'a' is meters. Thus, the final answer is a = 1 m. Understanding unit cancellation is crucial in physics equations for accurate results.
copperfox
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here's the question:

a = b/e
b = 1 kg m-1
e = 1 kg m-2

what is a? including units

I assume it's to do with cancelling out the units when you divide but I really don't know what the answer is
 
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copperfox said:
here's the question:

a = b/e
b = 1 kg m-1
e = 1 kg m-2

what is a? including units

I assume it's to do with cancelling out the units when you divide but I really don't know what the answer is

Hi copperfox! Welcome to MHB! ;)

Indeed. It's about canceling out the units.
It works like this:
$$a=\frac be
= \frac{1\cdot\text{kg}\cdot\text{m}^{-1}}{1\cdot\text{kg}\cdot\text{m}^{-2}}
= \frac{1\cdot\cancel{\text{kg}}\cdot\text{m}^{-1}}{1\cdot\cancel{\text{kg}}\cdot\text{m}^{-2}} \cdot\frac{\text{m}^2}{\text{m}^2}
= \frac{1\cdot\text{m}^{1}}{1\cdot\text{m}^{0}}
= \frac{1\cdot\text{m}}{1\cdot1}
= 1\,\text{m}
$$
 
Equivalently, $\frac{b}{e}= \frac{1\frac{kg}{m}}{1\frac{kg}{m^2}}= 1\frac{kg}{m}\frac{m^2}{kg}= 1\frac{kg}{kg}\frac{m^2}{m}= 1 m$
 
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