Homogeneous equations

Physical Quantities & Units - OCR A-Level Physics

Worked Example [3 marks]
Show that the equation \(v^{2}\) = \(u^{2}\) + 2as is homogeneous.
Show Solution
1
LHS

\(v^{2}\) has units ($m s^{-1}$)^2 = \(m^{2}\) $s^{-2}$

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2
RHS first term

\(u^{2}\) has units ($m s^{-1}$)^2 = \(m^{2}\) $s^{-2}$

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3
RHS second term

2as has units ($m s^{-2}$)(m) = \(m^{2}\) $s^{-2}$. The 2 is dimensionless.

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Answer
All three terms have units \(m^{2}\) $s^{-2}$, so the equation is homogeneous.
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