(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Suppose two objects have energy fluxes, f and f + Δf, where

Δf ≪ f. Derive an approximate expression for the magnitude difference

Δm between these objects. Your expression should have Δm

proportional to Δf.

2. Relevant equations

Δm = m2 - m1 = 2.5 * log(f1/f2)

3. The attempt at a solution

So the issue is that I'm not sure which of these solutions would be the better one to work with. However, I did make an approximation with the one as shown below and I'm not sure if it is quite accurate enough. Any assistance is greatly appreciated.

Attempt 1: Δm = 2.5 * log(f / f+Δf) = 2.5 * [ log(f) - log (f + Δf)]

or,

Attempt 2: Δm = 2.5 * log(f+Δf / f) = 2.5 * log(1 + Δf/f) ≈ 2.5*Δf

The second attempt seems more correct to me but I would feel more confident with a second opinion.

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# Homework Help: Energy Fluxes of Two Objects

Can you offer guidance or do you also need help?

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